03 Silverado Misfire, Rich AND Lean fault codes

hey guys scanner dad are here with my son Caleb behind the camera as usual we are at my brother's shop Danner's automotive in Bethel Park Pennsylvania and today we're actually working on a truck from someone who found me through YouTube I he's obviously local to our area we're in the Pittsburgh area and found my brother's garage and and brought it to him through my videos which is pretty cool the guys name is Patrick so Patrick if you're watching you may end up seeing your truck some day either on YouTube or on the premium tool not sure where this is going yet but our task today with this truck which I don't even know year I think it's a 2002 Chevy Silverado 2003 Chevy Silverado and I believe this was just purchased by this owner and there was a lot of parts that were replaced complaint is a misfire check engine light on although from what I'm told from my brother the customer's not feeling a misfire but that's the codes that setting and I think it's had a fuel pump I believe it was purchased not running and it needed a fuel pump to get it running Patrick you have to forgive me if I'm getting this wrong this is second-hand information but pump was put in it does run but then it had misfire and I think in an attempt maybe to fix the misfire codes it got all new injectors all new coils plugs wires things like that one of the things I noticed when I first started it I hear an exhaust leak up front and I believe we have some fuel trim faults in here too and so that's a concern for me having an exhaust leak way up there in front of the oxygen sensors that doesn't help matters either but let's start by pulling codes we're gonna go for a test drive see how it feels go from there all right so when I was talking to my brother yesterday he did mention to me that we had some fuel system RIT's fault codes and those are concerning to me more so than the misfire because in general a misfire is not going to cause rich condition faults even though you're sending unburned fuel into the exhaust say with an ignition misfire there's oxygen there too and it will cause lean conditions misfires in general most of the time will cause lean conditions with the oxygen sensor you can have a misfire say a mechanical problem with an intake valve that isn't operating properly that that you can have a rich condition I've seen case studies that guys have done I've never seen that myself but it is possible my point is this I see a misfire I see rich codes I'm going after the rich codes first now if those were lean codes with a misfire I may attack the misfire first as far as ignition injection things like that vacuum leak but this to me looks like possibly the rich condition is may be causing the misfire also the customer complained complaint is that he's not feeling the misfire even though it's setting 1 so let's that's weird it just disappeared but as I was talking my misfire code went away all right let's look at our fuel trim data B next up well no you know what before we do that I want to look at some freeze-frame data just get some parameters here when I was talking to my brother I was asking him for this info and you know freeze frame data can sometimes be not helpful and some of the data that he was given to me seemed to be that this is the case because this is the fuel system rich bank 1 fault and yeah I mean look look at your fuel trips short-term trim is 1 and minus 1 long term 2 and minus 3 and minus 6 those are not in a range at all that would set a fault code and so this is kind of what I'm talking about we can use freeze frame data but sometimes it's just not all that helpful it looks like so engine speeds 608 so we're at idle 12% throttle yeah we were definitely idling when this one set in close loop warmed-up engine 190 degrees so mass airflow at 7.4 I am concerned about the mass airflow sensor just going into this job let's see what the bank to Ritz fault it shows yeah again these trims aren't really matching the code there's positive 11 and 9 on the short-terms minus 6 and then two nothing crazy 1,500 rpm you're really not helping me at all let's see the engine miss freeze frame data and the trims Arleen during the mists which would kind of make more sense misfired lean condition but 11 on the long term 16 on the long term 5 on the short term 0 see this just looks like this was under load because maps at 3 1 6 engine speed 2,400 throttle angle 37% I don't not really all that helpful but it is something we don't want to forget about looking at I'm like squinting at the screen and I don't need to be I've brought my glasses yeah right now we're running rich so we have a bank one long-term of 12 in a bank to long term of minus 18 or minus 12 and minus 18 short terms are balanced they're around zero so I'm not liking that at all let me configure this that's awfully high for a mass airflow g/s reading so this is a this a six liter engine it it showed it on the screen I didn't mention it I would I know I I'm pretty sure it was this is a six liter engine okay so six litre engine we should be about six grams per second at idle on the mass airflow we're reading 7.4 all right this mass airflow grams per second it looks a little bit high to me so it's about 7.5 and bouncing around this is a 6 liter engine and so it should be about 6 so that could be our rich condition right there we have a an over-reporting mass airflow sensor one of the things about that number though I want to warn you guys about because I hear a lot of feedback from you is if you have an engine that is less than a 3 liter less than a 3 liter engine this mass airflow compared to leader of the engine we can no longer rely on as far as accuracy goes and I learned that recently from a class I was in the instructors name was Eric Ziegler and this was at the Super Saturday training event in Philadelphia and he was talking about that number and we all know that number so for example a 5 liter engine at idle you should have about 5 grams per second 6 liter engine at idle should have about 6 grams per second and so on so this seven-point whatever we have on this 6 liter engine to me it looks high right should be about 6 and I have seen engines I think the one killed that we did the mass airflow sensor on on the Hyundai or the Kia it had higher numbers it was like a 2 liter engine and it had like three point four grams per second at item when we were done those were good numbers and so what Eric had taught us in this class is when we get down to three liter engines or less that we can no longer use that number reliably so you guys need to remember that so a little tip for you guys this does look like an over reporting mass airflow to me my next step I want to raise my RPM and see what it does at a higher speed yeah this is classic contaminated math because as soon as I touch the throttle my long term numbers went positive although my short terms are negative right now that's odd we're still really rich it's like the memories not there I was thinking of a case study dirty mass airflow on a Subaru some other cars I've seen where they'll go negative at idle and then positive at higher rpms see where we are 2500 it's still real negative not as bad now so 2,500 is definitely better almost normal trims at 2,800 on bank 1 bank 2 is a little bit more rich we still - 10th feels real lumpy now doesn't it you feel that like I can feel a miss yeah and now my g/s numbers are at like 6.4 mm-hmm long-term trim still minus 10 long-term trim now I'm back ones minus 6 we were a lot different than that a few few minutes ago if I'm not filming tell you what I'm doing right now I'm pulling the mass airflow out and taking a look at that the the wires on that for you guys and for us I'd like to prove it before I go under the hood I don't know that that's a misfire that's just more of a kind of a rough roughness feel but fuel trims are now normalized it feels pretty good or it looks pretty good well not anymore - 12 these were known to get the alcohol and fuel calibrations mixed up on these GM's and misfire history on cylinder 5 is 22,000 misfire history on cylinder a's 58,000 so 5 & 8 for sure [Music] still again I don't like that vacuum Li not vacuum like that exhaust leak that we have up on this thing too does not help us when we're analyzing fuel trim data [Music] [Music] I'm just looking to see if we have a alcohol percentage listed on here that's where really what I'm looking for at the moment I don't see you know there's not a whole lot that'll make an engine run rich leaking fuel injector is too high fuel pressure leaking fuel pressure regulator mass airflow problem maybe a stuck open purge valve fuel tank pressure sensors at zero let's do a test here see if I can do a bi-directional test on that perché controls of Hertz I want to close the vent seal commands the purge solenoid to zero keeps the vent closed okay so I want to do this and watch these what we should see is our tank pressure changing because that sealed the fact that that's not changing is concerning to me let's gone to the hood real quick Gail if I want to check before we go tickets for a test-drive I want to check his purge valve real quick it's easy to check purge valve honestly my main concern is is it stuck open we can look at some fuel trim data and stuff too to help us but it's not what I want to do initially here with the electrically unplugged you should have no vacuum pull here and we do not so my concern of a purge valve sticking open causing our rich condition and then changing the amount of trim data as it pulls the fuel out of the canister it's time to be lean at times of the race I'm no longer concerned about that does look like all new coils I cannot tell if these injectors our new or not does not look like it we can do an injector phallus we're gonna do that alright so we've I'm choosing this test next because it's one of the causes of a rich condition is leaking fuel injectors and it's easy to do on this setup because I have a service port and I have the ability to bidirectionally control the fuel pump and fuel injectors with the scan tool and this is literally a two minute test because of the setup on this have a gauge connected with that no yeah no I think we're gonna go for a test drive but I just kind of got lost in what we were doing so these injectors do not look new to me I mean they could be may be swapped out I don't know I'm just gonna do it real quick injector balance test sir and so Caleb ought to describe this to you what we're gonna do is we're gonna run the fuel pump it's gonna get us up to a specific rest pressure and then we're gonna activate each injector for a precise amount of time through the scan tool and then we're gonna watch our pressure drop so if I ever you ever seen this test on things alright so injector balance key is on already so we hit continue what we're gonna see is that gage should we can ejector one yeah I need to exit out of here and before I do this test I need to start this and/or run the pump I'll start it I need to purge the air out of this system I don't know what the spec is on this car either that seemed to build kind of slowly but I'm not worried about low fuel pressure not with rich codes all right so let's try this again so we'll go injector balance ahead and continue doing injector one first nope I need to make sure that I'm getting this right so that's had like 40 by 48 48 down to plan on day 28 29 now we'll do the same thing for injector too we want the same starting point yep that's a little bit higher I'm gonna give that a second because we're about 48 yeah it's about 49 oh we drop to 28 continue Chapter three it's 28 we want these all to be the same so what we're doing is we're firing the injectors for an exact interval yep a little bit under 28 there for a second kind of nice to have this done off like an automated method that ones lower uh-huh that's six s twenty twenty twenty seven we're gonna do them one more time to number eights a big concern for me that pressures a little bit lower to start on that one has about the same yeah yeah and that's the one with the most misfires alright so here's what I'm gonna I'm gonna start this hold on exit this mode I'm gonna start this backup we're gonna burn all the fuel that we just spray it in the cylinders there's a reason the system only lets me do it once without cycling the key and starting it up so I'm gonna do that key off just letting it run for a second blow all that fuel out that we just sprayed in the intake all right now we're gonna do it again I believe we're done Kayla I believe we have injector issues I want to look at this gauge a little bit better so I want to look more straight at it so maybe if you get over my left shoulder and eyeball engage and do this again sector 1 remember both banks were rich but bank 2 was worse whoa holy crap I always sounded like 25 right just above 25 we'll call it 25 that's a little bit lower starting point that's these are different numbers that's 2 psi different right there that was down to 23 I need to make sure our starting points the same - yeah we have injector issues here are people that's so our first one was 25 27 26 right we're gonna end up doing this again and I'm gonna write them down we'll go inside - 27 are now 20 sorry 23 yeah I said those numbers wrong I meant 25 20 I decide I thought you were talking about the first time definitely have some flow issues here yep there's two psi difference on on this this is number eight was the worst on our last go-round it wasn't as bad that time how weird is that starting it up again [Music] [Music] [Music] I'm gonna do this again I'm not worried about the the differences that we saw as far as what it drops to this is a comparison from injector to injector so some of you have questions on why is it different I don't know air pockets fuel temperature don't know don't care what we want is the same pressure drop each time okay so first one and that's I'm gonna wait till that drops to 48 we got a little bit of a bleed down issue down here so hit the button if 48 and that dropped down to just under 25 right not quite 24 I mean my angles off and where I'm looking what it looked like to you it was 24 injector to we're gonna get this right at 48 that's a 40-year just above at least from my angle I'm going from my angle and I'm gonna hit it at the same point so for the last one was 24 that one dropped lower to front least from my perspective again my gauge angles off that was about half to 1 psi different between 1 and 2 which is not bad you want these identical though it's like holding I'm on baby drop a little bit more for me still a little bit higher than where we were on the other ones a little bit just a hair well if I'm seeing a 2 PSI difference I'm not liking it these should all be absolutely identical see we do have the lowest was to psi lower than that wasn't it we we hit 23 on a couple didn't we at least one of them I think I saw that's too much too much difference so part of our issue is is an injector imbalance this is number eight that wasn't bad that time but it's a stretch man seriously yeah like God it's not as bad as I thought and this one was wasn't it so now we're back to the math yes it's cold we could go inside we need a test drive this though I want to do a quick visual inspection on this math I don't like the injector balance results that last one to me we had the maximum that that I think you're allowed I have written in my book no more than one-and-a-half psi difference between lowest the highest but I have to be honest with you that spec I don't even like that they should be identical all of them and we have almost a two PSI difference on some of these injectors that's gonna absolutely be a contributing factor to our fuel trims being being messed up probably would have helped pull the air cleaner off plus things super contaminated not super but see if I can show it to you these ones are hard to it's hard to show oh yeah that's really dirty see now I'm thinking do we test drive it and get some before numbers before I clean it you're not gonna be able to see that through the honeycomb the resistors especially that top ones pretty dirty I need is a spotlight you have your light on you I don't know that you're gonna be able to show this Caleb the backside what I want what I want you to see when the camera would be the the resistor so the little cylinder part on that guy right there same there's one right there No and then there's one right there okay so see if you can show that that's the back side of it so that's what you want them to look like they're nice and clean and the problem though with our camera is it's not going to show the front side and this especially this top left one you can definitely see the blackness I can't I mean my naked eye definitely can see it and I don't want to take this screen out because I don't want to damage the screen but we're gonna we're gonna clean this just to see the improvement on the numbers and I said we should test drive it and maybe do some v-type testing I'm not I'm not doing that I'm just cleaning it will clean it look at some trim data uh-uh my bent brush is missing all of its bristles missing my brush we are in luck we're going inside you have I need some mouth cleaner and then I need you know the grease brushes like a little like paintbrush spur you got any of the any of those that I can put a 90 degree on so I can scrub the front of this yes I'm a freaking pack rat yeah can I can I bend it you don't mind mouth cleaner yeah all right um you're not gonna be able to see well what I'm doing but I'm spraying each of those each of those resistors those three and then I'm taking my brush I'm gonna go on the back side of it this would be where a light would help us you know what I'm gonna go get the light there's no way you're gonna see what I'm doing all right come here Caleb I see better he's using this to gently brush the front side of those resistors then I really couldn't get to otherwise spraying them is never enough one more Spray it one more time from the front what's your camera for a second well there's still some crap on their horse I could show it to you okay I like that let's go reinstall it see where we're at fuel trim why see if we have any improvement at all I still think we have a little bit of an injector balance issue as well we'll run that test maybe one more time after since it's cooled off a little bit one of the problems that you can have is um when you have hot fuel it tends to bubble and boil in the fuel rail as you're relieving pressure and that can cause inaccurate readings with that test so that is a variable when you're doing injector balance testing because as you lower the as you lower the pressure you lower the boiling point and so when you're doing that test and you're doing kind of a bleed down the fuel can boil in the rail and then cause some bubbling which then in turn it causes pressure differences I have to say if if this has any improvement on the negative trims this would be the first DM that I've ever seen cause negative trims at idle from a dirty math seen it on other models but never on a GM not once okay no before we start that redo this injector balance okay where it is one more time I don't think I started the engine from the last one but we'll Bri doing - it's not letting me it's gonna make me start it [Music] just under 25 just a hair under that's like just under 24 almost 23 for injector - I need you to write this can you write something down from me there you got a pen some write down I'm playing with gas it depends how much go ahead hang on all right so injector one we'll call it twenty four point five injectors - I'll want to call it twenty three point five okay what I got to sit here for yep say six more yep I mean I saw a snowflake out here it's freaking cold that one's 2023 that's number three uh-huh twenty three even mmm-hmm so I don't like the variation here at all at all you're not gonna grab the gauge anymore Caleb that's 23 as well for Danner come stand over here Caleb get back on the on the fuel pressure gauge well we're gonna do it again there look hold up man I'm already 23 that's five yes 23 so this isn't going to start for crap well it will I've been starting of each time that's like 24 and a half for number seven so we have a flow it there's a flow rate issue it's not drastic but it's definitely there and do you look at it all right last one that one's like I was like 24 when you look at the at the myth fire number 8 had the most when already had the most huh and that wasn't it low all right right yeah you're not over the better the lower would be more fuel flow yeah so I mean these are drastic so yeah 23 your max yeah you're Max's so we only have like well there's a maybe yeah and that's like right right on the borderline aspect that I've always used and was taught years ago is one no more than one and a half psi difference lowest highest but what I've seen on good systems they are identical across the board we have a flow issue with these injectors so I cleaned them off it was dirty oh good cat's brother good cats I'm gonna take or this exactly I'm gonna see how the trims look now that I cleaned them off I was just telling Caleb wrap now you flooded it yeah the coils look new I don't think the injectors are maybe he put used int actors in it I don't know so last thing we had a little Mike change there with the camera I was just mentioning I didn't like the injectors being a pound and a half difference lowest to highest it was weird that that number eight did have a really large pressure drop the first time we did it and then after that it did not so though it was weird number eight was the one I was focused on the most because of the number of misfires mass airflow did look contaminated cleaned it let's see the result of our fuel trim numbers now it's gonna be a little bit flooded from our last balanced test we haven't started it yet [Music] again we have an exhaust leak to up front which is not a good thing when you're dealing with trim issues so injectors I don't like exhaust leak I don't like but exhaust leaks gonna make it go positive not negative and we're kind of more focused on the negative trims I'm really curious to see my long-term trim memory right now is minus 18 on both banks I really want to see when this goes into closed loop what it does on the short term and the fact that it really hasn't changed I would expect to see these go very positive if we had corrected the rich condition based on the mass airflow alone and I'm not seeing that minus 14 minus 18 and I'll be honest with you guys I think this thing needs injectors or at least needs to have the injectors cleaned maybe an attempt to clean it yeah still very negative I work we're gonna go test-drive this my mouth g/s is about six I think maybe when we first looked at this and it was about seven and a half my rpm was higher and I wasn't really paying attention to that and I should have been because worth like 580 now and we'll be able to see in the edits what that rpm was because the higher the RPM obviously the higher your mass airflow grams per second is gonna be but we still have a rich condition going on here and I don't like the flow rate of our fuel injectors it's very possible that you'd have the one did we have one drop to 25 Caleb or were they all under 25 we had one or two that we're at 25 and so I think that those are probably the only good ones based on the on the trim yeah and the ones that we're dropping lower we're leaking fuel essentially we are driving Bank one long term just changed to 3% absolutely needs to fix that exhaust leak I think my brother said there was a broken bolt on the manifold so it's leaking right at the manifold so what happens when you have an exhaust leak upstream of an oxygen sensor is when you have that negative exhaust pulse you're actually pulling oxygen into the exhaust creating a false lean condition from the exhaust leak I know we're chasing a rich condition here but that could explain our imbalance between bank 1 and bank 2 and bank 1 is the side that I hear the exhaust leak on and bank 1 is less rich than bank 2 so we may have that being a factor as far as why we're seeing the difference to bank to bank but of course that can just be injectors as well doing a lot of the throttle run real quick wanted to see full rich on these oh twos certainly delayed pull over for a second here it bank to is -18 pretty steady - 18 - one more time a first gear wide-open throttle run [Music] like like that at all that sound was that a pop through was that behind me or in front of me it sounds like it was behind oh that's a clunk I thought it was a pop through the intake but it's like something in the drive drive line that was clunking yeah that's yeah that's not a I it sounded exactly like an intake backfire but it's something in the drive line yeah I'm not a big big fan of this this Mass Air Flow oh-two millivolts at wide open that it's not good do this one more time I need my throttle angle in here alright so first gear run my throttle angle at sorry Patrick did not need to do that [Music] we are not staying at wide-open three at wide open throttle like we should be so that is a lack of fuel not a rich condition opposite opposite so all that did was complicate matters we have there's a fuel delivery issue on this engine which couldn't put us back to the math it could put us to the injectors too if they're not firing properly as far as flow rate ghosts some that are may be restricted some that are leaking I don't know let's look at some of these numbers yeah I mean frame 320 is where I went wide open and net o to an upstream let's see what bank two looks like yeah it's like dropping lien stay here in the nice warm car I'm grabbing my laptop so we can do a ve calculation I mean it had good power you heard the tires squealing again sorry sorry Patrick I wasn't trying to do that I was just trying to get some wide open throttle numbers these are new tires too but I took took a couple miles off his tires Oh No battery's almost dead all right I was gonna start a desktop here but I can't I'll just have to let you see what I'm doing all right so it's a six liter take care is 57 without us 47:26 mass airflow of 240 1.69 then 57 degrees for intake air we are about a thousand feet above sea level a humidity of 30% probably pretty pretty close yeah so a ve of eighty-six percent that's just telling us our math is not the problem and so our Oh two s that are dropping lean can be a fuel pressure problem it is a new pump I didn't check the specs as far as what our fuel pressure should be on this I really think I want to put the gauge back on and do one more injector balance test and and I want to write it down this time and I want to do some snap throttle fuel pressure measurements to make sure our pressure isn't dropping and with the math looking good ve number-wise air flow wise we should be getting the fuel that we need based on the math and the fact that these o2 s between frame 330 right here that's where we started let me pull my TP s in yeah you see where I went wide open throttle looks like maybe I let off a little bit because the tires were or squeal and I didn't want to kill the customers tires you see during this run like all in here that should be this should be full rich on these o2 s and it is not and it is worse on bank two than it is on bank one it's kind of tough to make that call on the oxygen sensor but it is not full rich so when you see that you're thinking mass airflow low fuel pressure injector issues some other input you know map and not a huge player on this one the map but it is involved the map numbers look ok usually when you see that it's fuel pressure or mass airflow and and in this case I believe we may have everything pointing back to an injector injectors themselves not flowing right okay trims look better after it gets warm -6 [Music] don't feel a misfire when we were driving it that exhaust leak got a lot quieter once it warms up so not it not going to be a huge factor in our trims I guess the guys complaint is just that the light comes on he's trying to fix it I believe he's going to be putting a set of injectors in this to fix this car so see the bolt is missing in that location for that manifold and we do hear some exhaust leaks on that side this is bank one just drive by wire yes so I want to do some snap throttle tests I need to be able to see the gauge from inside the car I just want to make sure our fuel pressures not dropping off because slow that builds - did you catch that didn't like that just did it row real quick visual on my fuel line make sure it wasn't leaking I don't want to see this pressure drop that's what we want to see an increase that's good did not like that hold on I'm gonna unplug the vacuum line of the regulator come out here real quick can you doing pressure checks I'm stalling my last Rev that it went up and then came down some of that's because of vacuum and so what I like to do with vacuum regulators over here when I'm doing this test if I can if it's one like this I like to take the regulator off well suit or the vacuum hose off the regulator as soon as I do that you're gonna see this pressure rise their oppression went up to like 57 58 here's what me putting it back on right so now we're gonna leave that off we're gonna do the same test that we shouldn't have a drop and so what I've done is I'm eliminated for your eye any change in pressure based off of that regulator is no longer going to be a factor I stated that wrong any change in vacuum which affects the regulated pressure is not going to be a factor for this test now and I can watch my fuel pressure gauge so watch it we don't want to see a drop a slight drops okay but we don't want to see a drop that is a huge problem that is our lien condition right there watch it again that should not happen will we drop the 45 under load this is supposed to be a new pump Patrick we have a fuel pump problem we have a fuel delivery problem as noted by our wide open throttle Oh to test here's the thing none of that this fuel pressure drop is gonna make our fuel trim numbers go negative so I still believe he's gonna need some fuel injectors for that part of the job I think we have some some restricted slash leaking fuel injectors and we absolutely have a fuel pump delivery issue I don't know what the problem is as far as that goes yet but that's a problem but I ball I'm gonna crawl underneath and see if the fuel filters new or not but something's not good with this pump Dan or going the other side is it I mean the exact exhaust leaks and holic converters but it watch this fuel pressure gauge go on the other side I took the vacuum line off the regulator to eliminate any changes in pressure watch this yeah from 58 so and I noticed that all no attendees know the newer these the new LS ones they still need 50 psi for them but no no no no not like the not like the pop it style yep good question but we so here's what I noticed on a test or everyone's good yeah I noticed that my oxygen sensors do not drop I'm sorry my oxygen says there should be full rich it wide open they're not they're kind of fluctuating and that's what put me I'm like wait a minute something's off and so we did a ve test looking at the mass airflow I was worried about the math I'm no longer worried about the math but we have a fuel pressure that's dropping under load that's not related to the rich codes that we had now did you mention lean codes ever on this well he said lean but when i standed i saw rich codes the only thing I said lean was when I had looked at freeze frame data on the misfire and I saw that XT 6 miles per hour it's you know 2800 rpm whatever and I saw that too I saw the two positive 16 and 11 which is weird so it's very likely a 65 miles an hour going down the road pulling a load that his pressures dropping to a point where the things going to start to maybe even misfire and set lien codes not rich codes now the rich code part of this I believe is an injector flow issue I don't like the numbers we had they're too far off we're right at maximum so we have two separate issues that dropping pressure gage is not our rich codes yeah now what's it doing in idle now as far as like it I'm minus six on long term right now - to I don't I don't that would bring more lien but I have seen dirty mass airflow sensors cause rich conditions at idle speeds I've not seen that on a GM and when I first started this I was 18 and 18 - 18 and if that was the case what I would wanted to see the short-term go positive immediately after cleaning the math and I did not see that I think this is more temperature related than it is the cleaning of the math that did anything you know I'm gonna redo the injector balance test one more time and write everything down I don't like the pressure drop that we have you said this pump is new he said the pump slew did he put a fuel filter in it I'm gonna do a quick eyeball but we multiple issues here but we've definitely identified a lean condition it definitely looks like it's been replaced recently okay you know it's nice about body lifts that's awesome what's nice about a body lift which is this big old puck right here that shouldn't be loose by the way is I can get right to my fuel pump connector right there no problem at all would this just real quick power and ground check on that I'm using my power probe again here Caleb because we're on a rusty frame rusty vehicle and I can go right to the battery to get an accurate ground you know know for sure that I'm absolutely reading a good ground instead of relying on my meter we use the power probe a couple of adapters for the power probe so I can use it kind of like my multimeter so I have a an adapter on the end and then just a cable and these were part of an accessory kit that you can buy for the power probe and then we make sure up here see let's get rid of that beep yeah twelve point two nine okay pretty corroded battery you just want to make sure we're getting good good numbers all right going after the gray wire first at 13 5 and then I want to make sure that that's not dropping comfortable with with that and then the ground should be okay pump ground 0.4 that's a little bit high alright so I want to see that when I rabbit okay I don't mind point four point four is a little bit high but not enough to cause an issue in my opinion so he either got a plugged up filter I can't tell just by looking at it or he's gonna need to put another pump in this I just went one pin down that's your float level 1.38 volts and then this would be float ground on the orange that's the purple wire by the way you're sending unit or your float that should be the float ground 0.1 of a volt and that's how I can tell when I'm doing pump circuits like this without a wiring diagram that's how I can tell which one the pump ground is and which one the sending unit or float ground is and it's simply based on the voltage level and you see the I moved it back to the pump ground you see we're reading point four for that pump ground and again like I said that's that's a little bit high I don't like that but I'd like to see point point 1.2 maybe but this is a higher amperage pump as well these things run about 10 amps of current and so that's not necessarily bad get you're off real quick fuel pump current measurement this grounds ok dinner yeah I'm gonna go going over the gray wire Caleb this is the punky wire okay whoops I switched it to a 40 amp yeah why is it not reading with my aunt probe there's nothing like fighting equipment failures my amp clamps messed up seen this before with my varus and that's that the scope gets a little funky sometimes you got to reboot it all right all right again what the hell why is the tank pressure sensor not even plugged in how was I getting tanked pressure readings before why's my amp clamp not working Caleb I mean I know I have amperage on this damn circuit something's broke something broke Caleb what an amp clamp yes please yeah so as far as where I'm at right now I think he needs to rectify this drop in fuel pressure before he does anything else I'm gonna secretly switch mine with yours yeah this one's working to fix my app clamp now Caleb come on the punk ground wire you can go on the feet or the ground does not matter invert this ten milliseconds pause that zoom out so we're averaging seven to eight amps of current you know the waveform looks decent there is some uptown oscillations in that but I'm not too concerned about that I don't think it could indicate a little bit of mechanical binding issue not a hundred percent sure on that you know what I want to redo this test I'm gonna drop this down to a 10 amp so we see it a little bit better with more detail pause that zoom out you see what kind of rpm we're dealing with my truck will draw runs at about 9,000 rpm which is a lot more than than some or I should say most and it should be an 8 bar pomp probably maybe use this low one one two three four five six seven eight back to one this might not be you'll find a unique characteristic of this kind of tough on a newer pump that should be eight eight bars right there at a time and that's in 6.8 nine milliseconds so my cursor placement here I'm not really sure that I like it three four five six seven yes that's 10 I mean it could be a 10 bar pump this is not common to see that okay I think I like I like that little notch in that one that little notch in that one I believe that's one rotation that's like 12 what the hell a real hard time with this one okay we do this let's go volts DC will do some math or an AC couple this that's gonna allow me to really zoom on this waveform you guys want to know how to use the purpose of AC coupling on a scope this is it right here just allowed me to zoom in on this butter go from there so they're count them one two three four five six seven eight nine ten we'll call that a 10 bar pump and that thing is rotating at what 8.36 milliseconds is one rotation so 60,000 divided by 8.63 this pumps are on in at six thousand nine hundred and fifty two rpm not nothing you know that's bad I don't have a problem with that but something is going on with it I think mechanically if you look at it it just seems like it has some mechanical binding going on there to me that could explain our our low-pressure issue giving this a ground right to the battery so this is going to take the tool I'm connected to ground this should yeah so I dropped it down to point two so from point four to point to 200 millivolt difference see if we had any amperage change yeah we definitely do so I needed switch to the feed side though Jumma ground current so we're going from about seven amps average when I ground this it's not changing really at all I just didn't like the point four so live were seven point one average and now I'm reading point two on my ground and I take that away seven amp so I'm okay with the point four it just seemed a little bit high to me for the efforts we had totally fine with the pump ground we have a pressure draw power and grounds are good leaves us to a mechanical issue either inside the tank itself something's wrong maybe he pieced the pump together didn't put something together right that's possible or two we have a plugged up inline filter although my amperage is low and rpms are in a range that suggests it's not a plugged filter but that's it that's the only other causes for this pressure drop one more time go back on the other side Caleb ready 58 would that drop to hide my head was below the - I was around 45 years my foot this time should never see this never see this on a fuel pump ever 45 huge drop huge job alright so absolutely this tanks got to come down and over he's going to change his fuel filter my suspicions based on current flow it's not a plug filter because if anything the amperage is a little bit lower than I expected to see my truck runs about 10 amps and I run a six liter engine - although mines in 2009 this is 2003 i I think something in the tank for sure one more time injector balance test we're going to do and we're gonna wrap it we're done alright injector one why am i reading a 51 psi rail pressure now could be temperature and this is the hard part about temperature changes things like this 51 to 30 right 51 it wasn't right in 34 all three of those but there was subtle differences barely less than 30 yeah there was a couple that were like with within a half a psi that was like 29 maybe 29 and a half 31 I might not have waited long enough the presser was maybe a little bit higher on that one it's hard when you don't have the exact same starting presser it's thirty one more time [Music] plug our vacuum hose into our regulator before I forget that won't make a difference on our balance test because there's no vacuum but all right cylinder one like different pressures every time I think his his pump 53:30 29 on that one 29 at cylinder - here's cylinder 3 there's it's only 52 now 29 it's number seven I was like 31 wasn't it yeah 31 yeah so we have an issue for sure still with a balance about a one and a half psi 30 number eight was okay though so look at my numbers from both times doing them so your highest or your most restricted it only dropped to 31 on cylinder 7 and then the lowest say 29 and a half on cylinder 2 I'm sorry the lowest would be 29 wouldn't it hard you know hard to say which ones are restricted or leaking based on these numbers but the fact that we have a 2 psi difference I mean maybe not quite these 29 s where they above 29 just a hair so still I don't like these numbers don't like these numbers and I think therein is gonna lie you're you're rich condition you know it's possible that 31 is what we want to have and the rest of these are all leaking some which is causing slight rich conditions i it's hard to say don't like those numbers so what's the call what do we do well first of all I would like to see this truck back after he fixes this fuel pressure issue I'm gonna tell him to drop the tank I don't think it's a plug filter you can try putting a filter in it and I can instruct him on what to do on the fuel pressure test that we did powers and grounds are good back there absolutely absolutely something with what he did but the problem with that is that's not gonna fix our rich codes we have I don't like the injector balance we have at least a pound and a half difference and that's the maximum and they should be identical so we have a flow issue with the injectors whether he's gonna put a new set of injectors in this or try some you know in tank cleaner is going to be up to him as well two separate issues I believe I believe once he fixes that low-pressure issue that old take care of her his misfire he's complaining about under under loads I didn't see lien condition codes although the customer states he did have them and that would make sense that he does have lean condition faults based on the fuel pressure dropping under load that also explains our wide open throttle oh twos not going full rich because we did not have enough fuel pressure these ones are difficult when you have multiple problem cars like multiple problem situations like this it can definitely be difficult what we don't want to do is sell the customer alt you know a whole bunch of parts just in hope so we're going to fix things no we have solid evidence on where we're going to separate issues a low fuel issue and then an injector balance issue I think between those two we fixed that you'll fix both of this problems both the rich codes the misfire code he's also got a manifold crap bolt that's leaking too and I hope we get to see this one back I don't know that we will this might be one because he's a do-it-yourselfer we advised him and and then he does the repairs and then he follows me so you're gonna see him comment on this video which is pretty cool so that may be the follow-up on this I'm hoping though we get some after footage we'll see if not guys I hope you learned something there was a lot of good testing methods in here I know we definitely enjoyed ourselves not but thank you so much for joining us make sure you like and subscribe and click the little bell icon so you guys get notifications on when I upload new videos guys thank you so much Caleb thanks for being my cameraman and we'll see you guys next time

Channel: ScannerDanner

Views: 187,756

Keywords: engine performance diagnostics, low fuel pressure, auto technician training, injector balance, auto repair, ASE L1, how-to, DIY auto repair, P0171, P0174, P0172, P0175, P0300, Low power, Misfire

Id: NKXY45Cjb70

Length: 73min 36sec (4416 seconds)

Published: Sat Dec 14 2019