Parts Cannon Special: Rich Running Chevy Truck P0172 and P0175

hey there viewers and welcome back to the south plain auto channel got a 2004 chevrolet it's a half ton uh it's got the big 4.8 in it money lights on and the guy tells me it has rich code so i think it's a 172 175 po 172 175 uh if i remember correctly could be wrong uh he's been battling this out they've done injectors saw all your stuff everybody would do you know fuel pump and pressure regulator and injectors mass airflow and oxygen sensors purge valve map sensor they changed it all and here we are now i will say this i fired this pick up to bring it in and it blew the biggest blue cloud of oil smoke i'd ever seen in my life and he warned me so it's been doing that for a long time forget about it so i did but it was pretty thick uh in the downtown area here with uh blue haze uh chevy smoke got the old all-tail hooked up they're gonna let it go through a fault scan uh we'll see where we're at and i do see and smell the frustration under the hood here and then we'll just base our diagnosis off the facts that we find along the way she's all done let's see here 172 175 so rich bank one bank two restraint codes hvac codes all right great well so let's go look at some live data um just kind of gather some yeah there's some stuff here let's see we're gonna go right in here and look at fuel trims uh see if there's anything coolant temp we're gonna want to look at coolant temp engine speed intake air anything that that can make it run rich uh we're gonna want map and here oh that's wrong i'll tell you that's wrong right now uh barometric pressure is wrong that could be a problem let's see oxygen sensors yeah we can grab those make sure everything's good get our fuel trim so let's fire this pig up all right i'm gonna take it a minute here uh did we get the loop status okay i think this is everything that's going to be important i know shining the camera at this screen is not ideal but it's what we have to work with folks so we're going to let it run a little bit here this really has me concerned that's interesting too our mass air flow seems to be abnormally high we'll let the idle come down as it warms up here our fuel trims already starting to make some correction especially on bank one that's interesting it's trying to pull back fuel still an open loop oxygen sensors seem responsive except for this guy seems still kind of at its bias voltage not a big deal mass airflow definitely seems too high so this is concerning this is concerning so that's very interesting fuel trims are pegged out i think i hear a vacuum leak human yeah i definitely hear a vacuum leak and it's on this purge valve i don't know i doubt the camera's picking up but i can it's quite obviously making some sucky sucky sound there i assume because it's missing the rest of whatever goes under that bolt shouldered bolt that's not going to make a lean or a rich condition and so right now fuel trims are pegged out short-term long-term that's really bad coolant temp looks okay mass airflow is definitely over reporting remanufactured junk let me grab a light yeah map sensors aftermarket purge solenoids aftermarket mass airflow some remanufactured garbage well we got a good place to start folks i'll tell you what folks known good i got a map sensor here for chevrolet i believe on these kion engine off our map is also our barrel which it should be you know so kion engine off manifold pressure should be barometric pressure so we could test but i need to get a step stool we could test that uh current map sensor or we can take five seconds and plug this in because that's quicker than testing [Music] i'm gonna unplug that one i'll plug that little guy in i'm going to turn the key back on we're going to see what barometric pressure is go back in here back into our field trim we'll probably have to pick out our list again uh we'll just go right to barrow where it was down towards the bottom boom look at that 14.07 not 12 psi so that's a problem great i tell you what let's be let's be mr nice guy you think i'm a nice guy in this though huh yeah i can be or i am i'm a pretty nice guy right most of the time i miss though when i'm not being pretty what'd you say trinity what'd you say gosh we've got to use the uh little rubber here folks mine didn't have one on it stick that in there oh good keep that in there all right guess what else i got folks mass airflow for a chevy huh where is this guy got stuff kicking around we got to get rid of the remanufactured junk here what's interesting is the amount of parts that they've thrown at this vehicle to fix a problem that they still have i don't know it's hard to explain i assume that this thing got injectors and oxygen sensors and mass airflow and maps and all the parts that it got because of this problem now i could be wrong i didn't uh i didn't quiz them that heavily on it maybe this these parts were changed to fix another problem but created this problem so yeah that's obviously uh some kind of remand i've just got the old rusty krusty oem which is always better than remand remand mass airflow sensors usually you need to buy them by the dozen so let's see we'll slip this one in i'm pretty sure this is a good one famous last words that's not something you want to hear from your heart transplant doctor gosh okay hopefully it's the right one i think i think these are the same like 99. 506 somewhere he's in there it's got to be all right just fired it up let me get the same let me move you around we're going to get the same data that we can now i could we could be totally wrong in this by we i mean us but we got to be getting better so barrow's good map looks good let's hit our mass airflow engine speed's still up there a little high she's still cutting back on the uh that's pretty wild i would have thought we would have made better corrections by correcting the barometric pressure but she's still cutting it back let me unhook the purge zone right here just want to make sure it's not pulling in fuel vapors very interesting here folks uh very interesting all right so that's pretty interesting folks uh map is working correctly now the idle has come down mass airflow is working correctly uh correct readings there's no fuel being drawn in from the purge which is a possibility you know where can we get this extra fuel uh things we have to think of are also oil how contaminated is the oil you know drawing through the pcv system you know past the rings obviously this engine is a massive oil burner you know so that's something we have to think of also kind of keep here in our back pocket i did remove the pcv hose right here right off the intake plugged it off it only changed it four or five percent went from 30 to like you know 25 percent uh so it's not all coming from there so this is pretty interesting now the things we have to uh other things we have to think of too is you know fuel pressure is fuel pressure too high you know there's been so many parts thrown at this thing could have wrong injectors in it for all i know um i don't think this is flex fuel never had an issue with the older ones with the flex fuel sensors i think that were underneath i don't really know how they function if that can be uh you know if that can screw something up also that's something we got to think about rich codes are not that common and when they are it's typically over reporting mass airflow purge valve stuck open some common stuff so i'm pretty surprised to see some things that are broken and reading incorrectly that ultimately haven't made a poo of difference so let's do this here fellas the truck's pretty rough i just looked underneath it there is not much left to it um so i don't know how much time we'll invest into it that's always up to the customer but see if it's a little bit of a baseline what's happening here [Music] let's uh see where we're at with fuel pressure let me just turn the key on and we'll just kick the pump on i'm just turning the key on there when it's about 40 40 to 45 expect this thing to be about 50 running okay let's go ahead and fire it up about 50 psi running that's what i would expect that doesn't appear to be abnormal and i guess the other thing that's uh noteworthy is the fact that it holds pressure about 45 psi so that seems to be good um i'll tell you what you grab a rag here i didn't uh [Music] let's just give a little whiff shall we of course now my hands are soaking yes go like this it's not over full it's down about a quart typical gm you smell it it just smells like oil doesn't smell super gas soaked so this is interesting so the only unknown variable here are the injectors now i see they must be of the best chineseium there is no numbers no identifiers no nothing on those injectors that can help me to tell whether or not they are the correct ones um they sell you know a lot of this crap on ebay and stuff where you know you get 32 injectors for a nickel and you know guaranteed to fit your vehicle i'm going to have to think about this for a minute folks i think we're running out of options running out of logical things that can cause or induce a rich condition to this degree unwanted fuel from the purge incorrect map sensor skewed mass air flow fuel pressure too high um pcv system pulling in vapors making it run rich or just base engine mechanical uh where it's pulling you know tons of tons of oil past the rings and which you know like i say this thing ripped a big cloud of smoke it's not blowing big clouds of smoke sitting here uh even prior to the catalytic converter heating up so i'm a little doubtful uh about that about base engine mechanical you know causing you know an induced rich condition to this degree on both banks i'm gonna shut the camera off i'm gonna think i'm gonna do some poking i'm gonna ask google what's wrong with it see what she says and then i'm gonna talk to the customer probably before all of that to ask them when the injectors came into the loop here in an effort to fix this problem or where they put in and then this problem was created that's that's going to be a key piece of evidence and then a customer where did you get them and do you have a part number so we can verify i think we're on that road one other thing that can be a concern folks is software do we have the correct calibration id numbers per vin i went on gm cal ids site here to make sure everything coincided the vin number versus what gm says it should be program calibration numbers cvn numbers and everything matches so it is the correct software for this truck and for that engine so that that's always a concern also can't get a hold of the customer folks um and i can't think of anything else that would induce a rich condition i really want to go down to wilbur to pull the bath who doesn't sponsor our show and just grab a whole fuel rail and just pop it on here just to see um injectors newer about 100 bucks a whack you know if you get legitimate good ones you know like i say they got the fleabay ones but i'd really like to know the series of events here because it's quite peculiar that we've got the problem on both banks and we had some issues that we corrected which is weird also i need to make a decision kaboom just like that went down to wilbur still won't sponsor us and i got these i didn't have time taking long bit of a hurry i did call chevrolet with the bin number of the vehicle that i took these injectors off and had them run this vid number for the vehicle that we're going to put these on in about a half a second same number stick around modern television great you don't have to sit through the boring repairs of swapping out injectors so they're in they're tightened up i think everything's good fuel lines oh you know what safety third where is it right here almost forgot this that would have been catastrophic in the event that this blows apart there's that i think everything else is plugged in and hooked up okay let's uh cycle the key here folks could be wrong still but i got my suspicions [Music] let's make sure fuel's not going pee-pee everywhere i don't smell it let's see how she starts now let's go have a look at beta fuel trim hey what do you know what do you say huh that's what happens when you put cheap junk chinese injectors in them from the ebay i say we're fixed mass airflow engine coolant temp engine speed map barrel you gotta follow the facts folks so i never did get a hold of this guy so i couldn't be burning myself because i didn't get authorization to fix this so if he tells me to pound sand guess what i'm out some money and some time wouldn't be the first time though because i know you guys wanted closure and if i told you that i suspected that the injectors are the only thing left you wouldn't have believed me interesting that our mass airflow is still slightly high but not enough to cause a problem better than eight grams the old one was uh but our fuel trim says it all this engine is running absolutely perfect we are as close to zero as this old chevrolet is going to get with the miles and stuff that's on it plus the amount of fuel that's probably in the oil i'm happy and i call it a fix these are uh that's something on there moto most plus m-o-s-t plus i believe is what it says uh nothing i've heard of before i think that's what it says m-o-s-t yeah m-o-s-t plus something i'll tell you where they are right now j-u-n-k junk i hope you all understand uh what has happened and the series of events we took to get to where we're at barometric pressure was screwed up because of the map sensor which is where it reads barrel from kion engine off the pcn looks and says hey you know where you at here here i am this is the elevation i'm at and of course it takes those calculations also uh during driving i think it takes them during wide open throttle events perhaps so let's say you're up in the rockies and you're down here in the rockies and you're going to get up here in the rockies well the you know the elevation difference is whatever the difference is and you know you're giving the chevy the full throttle on the way up and it may take some calculations from that i know ford does that and they calculate barrel through the mass airflow i'm not sure gm strategy i'm just making stuff up right now but that's what i would suspect some of them have they can sense barrel inside the pcm i think honda's pretty pretty uh famous for doing that having the barrel sensor built into the pcm instead of using map but i think they also make them relative comparison so key on engine office says hey you know does the boost sensor match the map sensor which matches the barrow sensor so they'll use it for some redundancy like hey you know if one of these fails it might flag a code and then use a default strategy of one of the other sensors so keep that in mind mass airflow is obviously skewed a little i'm i'm just gonna we're gonna keep that one in there we're gonna keep the oem in there we're gonna keep that map sensor in there and then obviously the ultimate fix with our fuel trims here uh as we can still see our beautiful worthy fuel injectors if you want to see some videos on field trim and how to understand it i think wells electronics or wells ve ngk now mike becker over there i think he does some great videos on fuel trim uh you know go over there check out their channel sometimes we just jump into it because we can't explain each thing as we go even though i sit here rambling at the end gotta call this guy see if he wants to fix now shame on me but at least you know i gotta put all his little junk parts back in at least we know when he wants the job done uh but we won't do that i'd really just give it to him then put the whole crap back on because we know and what i do know is i want you to go in the comments section the comments the concerns the facebook the bell ringing the insta the subscribe button whatever else you do when you're there and just remember if you're responding to it you can do it thanks for watching [Music] bonus footage i got one of these was at the junkyard too and this is what is missing off the perch it just goes on the bottom it's a hunk of rubber because it uses a shoulder pull and we should resolve our sealing issue that we have down here so we'll put that shoulder bolt in there and actually have something to hit against now anyhow for what it's worth

Channel: South Main Auto Repair LLC

Views: 237,666

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Id: 0aC4If9sFuk

Length: 22min 12sec (1332 seconds)

Published: Mon Mar 28 2022