Direct Injection, Problems and Solutions | The Fine Print

[Music] welcome to the fine print series today's topic is about GDI or di gasoline direct injection by the end of this video you're going to learn about what it is why it was created the benefits the pros and the cons and if you are an owner of a direct injected car or direct injected motor you may have some issues with it and we're gonna cover things you can do for preventative maintenance and then of course if you have the issue how you resolved it so let's take a deep dive into this topic now first you have to understand why direct injection was created and the primary reasons are fuel economy standards and emissions regulations something that did not exist forever ago when the internal combustion engine was created and that's really the big problem it was never designed for all these types of control devices and that's why things have gotten so complicated with the modern motors and why so many people are bandwagoning the electric car era direct injection it's gonna sound pretty scary but really all it is is when you fill up your fuel tank your gasoline goes into a fuel tank there's a pump in the tank that moves it through the hoses all the way through the field lines through the front to the front of the car if you have a front-engine car and it moves the fuel all the way to a low pressure fuel line to a high pressure fuel pump this pump is cam driven it charges the fuel along these fuel lines down the rails down the lines into the injectors and here is where the fuel is delivered into a direct injector it's called direct injection because the fuel injector is sprayed directly into the combustion chamber there's your spark plug there's your fuel and that's what causes the combustion process these are your intake valves that open and close that is your piston and that is the combustion cycle so direct injection or GDI is nothing more than an injector being sprayed into a cylinder now there are different ways to deliver fuel electronically before direct injection really what the mainstream is right now still with most cars on the road is PFI or port fuel injection so let's take a look at how port injection works versus direct injection port injection much like direct injection you fill up your tank there's a fuel pump that sends fuel through the fuel lines to the front of the car assuming your engines they're directly to a fuel rail and the fuel rail will distribute fuel to the port injectors which then spray into the cylinder head but this time instead of spraying directly into the cylinder you're spraying on the backside of the valve train through the openings of the valve ports into the cylinder that way so there is fuel constantly being sprayed on the back side of these valves there is no injection into the cylinder directly and you can see the way that the fuel flows here also you do not have a high pressure system that's cam actuated to build it up so you only have one fuel pump four port injected cars which simplifies the process quite a bit now you know what port and direct-injection looks like and how it works there's a third iteration now Toyota is kind of mainstream this on their cars and more and more vehicles that they have are starting to do this now Ford is also starting to mainstream this on their cars and moving away from direct injection only now it's of course it's not gonna be on every motor because there's a lot of costs associated with it but this is when you combine port in direct injection you have a port injector here that sprays into the cylinder head and you can see that it sprays onto the backside of the valves this is where the fields going and then you also have direct injection here which sprays into the cylinder directly now every single manufacturer is going to tell you how their engine design is better than the other guy how they've done this and done that well really that's great until you're an owner stuck with the car out of warranty and you have to deal with all the crap so I'm gonna just discuss some of the pros and cons and what they've been able to do with direct injection that is really impressive and some of the things that just flat-out suck now it's time to talk a little bit more about how this works in the advantages of direct injection and this is a 3d model by Hyundai for their direct injected motors now let's go back to how this works a little bit you have low pressure fuel coming from the fuel tank pump into this high-pressure module that is cam driven as the cam lobe spins this it creates high-pressure fuel down the high-pressure line all the way to the direct injectors and you need high-pressure fuel because you're spraying it into a cylinder these injectors are very high-tech much more expensive than port injector port injectors themselves because they need to be able to stand to a high temperature a higher flow rate and of course well they're inside the cylinder so this fuelling technology combined with modern ECU's or computers and cars have allowed manufacturers to do things they couldn't do before much like your smart smartphone you just have to walk around with a laptop or have a desktop computer car computers are so fast now that they're able to control specific areas of the combustion process and that's what this all is all about putting a fuel injector inside the cylinder allows them to either create more power or to burn fuel more completely there's less wasted they can use less fuel and that's and obviously the huge thing here is it can lower temperatures of cylinders it can create more power and torque and alternatively they can change the modes by changing the way that the valves are operated they can change valve overlapped when they intake valves open and closed based on your cam phasers that can infinitely adjust and all of this computer control of this requires something like direct injection without having the specific control of your fuel in the cylinder they couldn't do all these things to give you the fuel economy and the power trying to create the best of both worlds now if you didn't remember your port injected motors which I'm going to show you again have fuel injectors that spray on the backside of the valves which have a natural cleaning effect it creates the spark in the fuel and the upper part of the head or the motor with direct injection you don't have that the fuel is isolated from the valves and only sprays into the cylinder itself now with both port injected and direct injected motors it really is the same you have your Pistons with rings and what you have is a natural side effect of the combustion process is what's called blow by and as this piston moves up and down you can have unburned fuel and oil vapor that can blow past these rings and back up into the head space or the crankcase of the car this happens with direct and port injection because you have pressure that comes up it's just natural for some cars in some cars it's worse it just depends on what type of motor you have it no motor is the same but so what what both cars do as a strategy as as that pressure moves up they need a way to ventilate it out and that's what you call a PCV system and that crankcase ventilation system has a port on the top up here that will ventilate that unburned fuel that oil vapor that pressure so it doesn't build up in the upper part of the motor and what it does is a part of the emission system is that PCV system will reroute that unburned fuel and oil vapor back into the intake manifold to be reborn' during the combustion process which on a fuel-injected carport fuel-injected car it's not a big deal because as that air comes back in here in from the intake manifold with that vapor you have fuel that washes off these valves here when you have direct injection as that PCV system is shooting back the oil from the intake manifold back into this valve train here all that crap is building up on the intake valves and there's no way to wash it off and that's one of the primary problems with direct injection you're not getting the cleaning effect from from fuel and that's why like companies like Toyota and Ford are now doing port and direct injection because you're getting that cleaning effect and you have even more tuning options with having both of course that leaves you with two fuel injectors for per each cylinder but you're getting the best of both and you're able to do more emissions tricks more tuning tricks cooling tricks so if you just have a direct injected only motor you're going to have this valve train issue now if you take the intake manifold off and stick a camera down those holes to the intake valves this is kind of what a port injector car would look like the valves are extremely clean or after a cleaning of course this is what intake valves on a direct injected car will look like after 30 to 60,000 miles depending on the brand depending on the motor it's it's extremely variable but eventually this is going to happen the other thing that it can cause and it's worse on turbocharged direct-injected motors is depending on the manufacturer that turbos they use oil can leak past the turbo seals and then get into here as well so it's like a triple threat so with no way to wash this off this is the end game this is what you're gonna have to deal with as an owner of these cars over the long term and the best part is and this is the fine print manufacturers come up with this because they are have to follow the regulations they have to meet these certain numbers so in a lab when the motors new look at everything it can do it can be more fuel-efficient you can create more power it burns cleaner and then you get it out on the road and you put miles on it and you're stuck with us because manufacturers aren't paying to clean these off proactively for you if you have a DI motor with this problem you're depending on where you take it you're gonna pay anywhere from six hundred to a thousand dollars depending on how bad it is some cars you have to do this every thirty thousand miles and if you don't do it well that's the best part it's creating the exact problem that it was designed to prevent poor fuel efficiency loss of horsepower you can have check engine lights misfires more emissions created from all of this soot and carbon buildup because these valves cannot operate and open and close properly you can't get enough air in because the air turbulence is all jacked up in here from all this baked on soot it's really frustrating and this is kind of what everybody's pushing is the new thing in modern cars and this is why we talk about this a lot now before I get into the preventative maintenance side I want to address this people ask all the time how is it that the cars in the 90s and early 2000s and 80s could get 40 50 60 70 miles per gallon and here's the thing they were able to do that in fact if you took a port injected motor right now and you ran it lean like the lean-burn motors of the late 90s from Mitsubishi and Honda you could legitimately get 60 70 80 miles per gallon you might wonder well why do you need direct injection well the problem with running port injected motor saline and they have done this is they can't meet emissions regulations anymore they create too much NOx emissions which are now you know those levels need to be lower and lower and it requires more emissions control devices more expensive catalytic converters EGR cooled EGR wideband o2 sensors all these supplemental things to make sure that yeah you're getting great fuel economy but how do we control the emissions and that's where it became a losing so now you have manufacturers well now we can spray fuel directly into the cylinders it kind of we can control the emissions that way we have a much better strategy at doing that and and I'm just saying this because if you're an engineer or you're a car manufacturer it's not like they're doing this on purpose their hands are tied they're trying to take something that is totally old-school and putting all this new technology and in hoping to meet all the regulations and of course meeting customer expectations which is like the worst part we're all a bunch of complainers so now let's get back into how can you help prevent this there's not a lot you can do from a manufacturing if you own a car that has bad blow-by and you have oil seals that are leaky and you're constantly having this issue well you're gonna be doing a lot of cleanup so here's a couple things you can do to kind of help prevent it especially if you're gonna keep the car long term I stress this enough you're gonna keep it you're out of warranty there's a few things you can do the first thing is oil catch cans something like this radium can and it doesn't matter what brand you use basically what this does is it runs in between the PCV valve and the intake manifold and what it's designed to do is to catch and separate the oil and unburned fuel and send back clean air that's filtered back into the intake manifold so you don't get the sludge and what the nice thing about these catch cans is if you get a good one you can separate them you can catch the oil and drain it you just drain it every time you change the oil the thing with these catch Kansa they need to be sealed because the PCV system is under vacuum if you screw up the PCV system we have a leak of vacuum link you're gonna affect engine performance because the tuning is designed around having vacuum if you have a vacuum leak if you don't use a good can it's gonna affect your idle your fuel economy all these other things and you need to have a baffled can if you don't if it's just an open can you it's like not you don't need a pop-can if you put like a tube into a pop-can and catch it it's not going to separate the oil and the unburned fuel from the vapor and you're just going to blow it right back in so you need either a like a scrubber or a baffle inside to supper Aaron oil if some manufacturers are putting arrow oil separators into their PCV system and it doesn't completely remove all of it just like this it's not going to completely remove all of it but it's gonna remove 95 plus percent of it the next thing that you can do to help with this is you know people talk about using fuel additives fuel additives will do nothing for a direct-injected car except keep the direct injectors clean and this is the next thing you should use fuel additives if you have direct injection because these injectors are a hell of a lot more sensitive than Porton jecht airs not only because they're exposed to extreme high temperatures but because they're exposed to a hell of a lot more carbon buildup that can get into the nozzles that can block them can affect fuel flow and if these things aren't blowing clean then you're losing efficiency and they're much more sensitive to it than Porton judders again so you might even want to you really don't want to do this but if you had a real problem you could send these out to a guys guys like Toronto injectors where they will put these on a bench spray them clean like as you can see in these videos you can see how that they clean the injectors if they're completely clogged and this is gonna become a much bigger issue and it's a bigger issue with DI so you're gonna want to run injector cleaner more often to keep these bad boys clean now you might have noticed a common denominator here oil blow by through the PCV system or the oil seals in a turbo so it makes sense to talk about the oil you use in your car specifically Noack evaporation loss or oil volatility testing the no act test is pretty basic you put oil in a vacuum and you heat it up for a certain amount of time and you test how much evaporation takes place in the oil based on the percentage the higher percentage of evaporation the worse it is for a vehicle like we're talking about so what do you do well here's the problem if you go to a dealership for your oil changes or oil changes in general your brand or your manufacturer has an oil contract with whoever they put the oil in their car could be Castrol it could be Mobil shale you don't really worse yet you really don't know what's in the oil they're not going to publish the oil volatility numbers so you have to get you have to go out on your own do the research in most Group fives which are true synthetic oils will publish their oil that volatility percentage and it seems like through the studies I've read you want something less than 7 percent oil evaporation or 7% oil volatility again the lower the better now here's the other problem as cars move to 0 W 20 0 W 30 or even thinner than that's coming out most those oils have over a seven percent volatility that's because they're thinner so if you're really concerned about this specifically if you have a turbocharged direct-injected car then you might want to consider looking at like a 5 w or a 10 or a heavier weight oil because statistically based on my research most of those oils have a lower volatility rate lust evaporation and it could help prevent some of these issues do your research on it though don't take my word in the last solution is kind of obvious you don't buy a direct-injected car you buy a port injected only or you buy a vehicle with this dual injection port and direct injection it just kind of solves this whole thing but it's more expensive and it's more complicated now if you don't want to run a catch can a good one and you don't want to deal with the oil trying to figure out a better all to run then you're left with this walnut shell blasting media because this is what you're going to be shooting into those intake valves into that intake manifold through the ports of your engine to clean out the valves every 30 to 60 thousand miles to keep it running optimal you can do the chemical way you can do the brillo pad you can use the drill way but this is one of the best ways to get the the valvetrain clean again and this is not something your average consumer is going to be able to do especially if you have those valves open you can spray this stuff directly in the cylinder and completely destroy your engine and this is the sad state of kind of what you're gonna have to do to keep this thing running right so there you have it you know how port injection works direct injection and dual injection and the benefits that it can bring better fuel efficiency more flexibility in controlling emissions but like any technology implementation there's some fine print and now you know it take care you

Channel: savagegeese

Views: 1,916,061

Keywords: di, gdi, direct injection, gasoline, problems, issues, diy, educations, cars, trucks, reviews, truth, carbon, cleanup, walnut, BG Products, Bosch, carbon deposits, intake valves, cleaning, ecoboost, Audi, Earthdreams, BMW, VW, Hyundai, Mazda, skyactiv, Mercedes, fix, repair

Id: xrLNDgrIw3U

Length: 19min 24sec (1164 seconds)

Published: Fri Feb 23 2018

Reddit Comments

[u/Sol-911]

Thank you.It was a bit long but helpful.