Chevy Duramax Diesel stalling? Most likely cause for intermittent stalling or non-starting problems.

oh oh man not again well I guess this is a good opportunity to tell you about the

problems

we are having with this truck so today I am going to go over a common problem on

chevy

duramax

trucks and if you have had a

duramax

for you may already Have you encountered this for some time, or if you haven't, there is a good chance that you will encounter this problem at some point. This is one of our work trucks. We have had the same problem with him at least twice. This could be the third or even fourth time we have had this similar problem and is applicable to al

most

any

diesel

engine.

What happens is you can start the truck and it will run briefly, which could mean it will run for a matter of seconds or a matter of minutes or at first this problem may be very spontaneous, it may be driving down the road or stopped in a stoplight and the truck just shuts off and can't run again until it gets to the priming pump, which is here where the fuel filter connects and re-pressurizes that priming pump. Once you repressurize the fuel system with the priming pump, then your truck will start and run again, sometimes it will run for a while, sometimes it will stop.

Right off the bat now I have to say that if your truck won't start at all, it could be this problem, but it could also be a lot of other things, so you might want to check a few other things to start, like the electrical system, make sure the starter relays and your fuses and all that are fine, but if you have a problem where your truck starts and runs and stops sporadically or starts and runs for just a minute or two or a few seconds and dies, there's a good chance it's A problem like this now, the essence of this problem is actually air getting into the fuel system and that's before it gets to the injector pump and the reason I say that is if you have a fuel problem after after it reaches the injector probe, then it is on. the high pressure side and if it is outside the engine on the high pressure side it will be pretty obvious be

cause

there will be high pressure fuel squirting out somewhere if the leak is on the high pressure side after the injector pump and is on the internal part of the engine, like some of the internal lines of the injectors or the injectors themselves, so you won't be able to physically see it, but what will happen is that the gasoline or

diesel

, sorry, will actually be injected into the caps of the valves. and will end up getting into your engine oil causing an overflow or overfill situation.

That is not the problem we are going to talk about right now, however, just for diagnostic purposes, you should understand that these

problems

do occur. before we get to the injector pump, which would be somewhere between the fuel tank and the injector pump, and

most

commonly somewhere around the fuel filter, so let's take a look at this quickly and I will show you the common problems. so this is your normal duramax fuel filter and it goes from the first generation duramaxes and this filter will go up to probably the model 17, not positive on that, but it lasts a long period of the first duramaxes, um, so it's a filter canister type um and this is where the water separator fuel filter is in a unit so at the bottom of here is when the water separator bolts to this when you have it apart from the truck the bottom of the water drain valve looks like this and it has a float like this with the sensor that will tell you, if necessary, well this sensor has an o ring, a rubber gasket around the bottom and it screws into the bottom of your filter this way, so this o- If this o-ring goes bad, it can suck air into the fuel system and will give you problems with the truck

starting

but not continuing to run, sometimes it may not start, there is a lot air in the system.

So another reason you might look for that could be a problem is that when you get a new filter, it comes with these two gaskets and this O-ring is the one we just talked about at the bottom, this O-ring actually goes in the top of the filter right here and it goes against the filter head uh and that's where the fuel primer and the diesel fuel heater is so if this ring, this o-ring doesn't make good contact sometimes you'll notice this problem When the temperature changes whether it's hot or not and your truck won't start or if it's cold and your truck won't start, you should re-prime the system anytime you have to re-prime and push the primer pump. to build increase fuel pressure to restart the engine, that's a telltale sign that air is getting in somewhere in the fuel system, so it could be from this lower o-ring or this upper o-ring if you recently changed the filter and tightened it. with a filter wrench you might even have a hole in the filter, that's un

likely

but it's possible so let me show you a couple of those are some of the simple things that could be wrong.

Let me show you a couple of other things that could be wrong, so this is a new filter head assembly for the duramax and we'll take a look at it, but here under the hood is where it is, it's basically on the passenger side behind. the driver's side wheel, um, so the filter bolts into this assembly like this, and you're in and out, the fuel lines come in here and they have directional arrows in and out, so a couple more reasons What could

cause

you this problem are several things with this. The filter head assembly, one of these two lines here, has hose clamps.

If those hose clamps go bad, it could suck air into the system and cause the fuel pressure to bleed or cause you to lose any kind of fuel pressure now that you have to restart the vehicle, of course you'll end up having to press this primer. 5, 8 or 20 times, if you have to press it 30 or 40 times, there is definitely a problem in your fuel line somewhere or in your fuel system before your injector. pump, but this is what would increase its pressure and allow you to start the truck again. However, the sealing gaskets here at the top of the filter or these hose clamps here could be bad.

This is your bleed screw and there's a rubber gasket under this that could also be bad and then long term with the duramaxes these pumps these pressure pumps here are going to go bad uh if you've never had this problem before this would be a good place to start, it's just to check all these accessories make sure there's no diesel fuel or anything that you can see that's wet on the top. Make sure there is no wet diesel fuel around these hose clamps. check your filter when you are in the truck, you can check your filter and make sure it is not wet. over here or wet or leaking down here make sure your drain valve there's an O-ring right here make sure it's not wet anywhere make sure it's not obvious where the diesel fuel is leaking because if the diesel fuel can come out then Surely the air can come in now if you've checked all that you can't seem to find it it's very possible it's internal so the first thing you can do is buy a rebuild kit for this priming pump and these rear wheels .

The kits only cost you about twenty-five dollars. They come with all the O-rings you will need and you have to remove them. You have to remove the filter head from the truck as if it comes off from time to time. I would have to remove this, which is the heater for the diesel fuel. You would end up taking it out with this screw here and then you take out these three screws and this whole assembly comes out with the spring and it has o-rings in there that can be replaced, you can put it all back together and make it completely sealed and functional again, about 80 percent of The times, if it is not one of the external problems that will solve your problem with the start of the installation of your truck. however if you have already done it and it doesn't seem to work or if you have done it several times or like in this case in this truck this truck has 280,000 miles on it and it has already been rebuilt several times The pump has it so in this situation we decided to purchase a completely new filter head assembly.

You can do it too. I called the dealership about these. It almost made me vomit. They wanted 500 for this filter head assembly so I said no thanks. I ordered offline, this is a porter, it cost me just over a hundred dollars to assemble. I've seen them as cheap as about $50, but I usually don't go for the cheapest piece I can find, I'd rather have something. that's a somewhat recognizable name so I decided to replace this fuel head assembly instead of just rebuilding the pump this time and I'll tell you why, since this truck has so many miles on it, I never replaced the heater under here as well. this heater and right here there is a check valve which is a ball with the spring loaded assembly just below here there is also a rubber opening with the spring and it is not serviceable it is a non serviceable part so when you do the rebuild The kit for this does not include the o-rings or the rubber plug part underneath, normally that doesn't break, but it is like a one way diesel valve that opens and allows the diesel to pass in a address. and not let it flow in the other direction, it is under this heater assembly.

I'm guessing at this point, if I put the time and effort into getting all of this out, I'll spend $25 or $30 on the rebuild kit. Well just go ahead and replace the heater assembly and all the non-serviceable and non-serviceable parts come with the wiring and electrical at the same time, as far as I know they have never been replaced before so that's it the route I am going to follow. this time to try to get this truck running so hopefully those are the first two things you can check and hopefully one of those things will be your problem.

There are a few other things you can look for if you are still losing prime, obviously you will need to check your fuel lines from the point where it enters this fuel head assembly to the tank, make sure they are not rusted, broken or leaking. , if they are rusted, broken or leaking. Air is definitely getting into the fuel system and it won't be one of these components or you won't know if it is one of these components until you fix the problem with the fuel line going back to the tank on the duramax no fuel pump in the tank there is only one sending unit for the fuel gauge on the dash the only thing that gets the fuel from the tank to the injector pump is the actual injector pump there is no lift pump on the duramax trucks in the older versions so air can get in to the system at any point so definitely check all the lines before removing all of this other than the fuel bag just get under your truck with a flashlight make sure there is no diesel fuel make sure there are no leaks nor are they rusted make sure these connections are good make sure there is no diesel fuel anywhere you can see if there is starter there if there isn't secondly you can start right here rebuilding this pump if that it does not work. change the whole set, you just want to spend a little extra money, move on, you can change this whole set to start, then chances are you'll know there's nothing wrong here as you move forward with your diagnosis, uh, the other things that you can find can because this problem is, for example, some electrical problems, uh, and let's take a look under the hood real quick and I'll show you what I'm talking about, so another thing that I found and that I heard is that if you're in the countryside or you're somewhere that has a problem where they might have mice or your truck will probably sit for a while.

What you might find is that here in your fuse box and not at the top is not what I mean, but I'm talking about underneath all this electrical center you will find that mice love to make nests. Below this are the two most common places I have found mice. The nests are under this electrical box and you will often find them right here in your air filter. They also like to make nests right there so you know they can access a lot of different places especially around the bottom so you can take this out and look inside to see.

If there is any kind of chewed up wiring underneath, I hear some people have problems with that, so if your truck is

starting

or running for a bit and then stalls, you can check that, of course, check all the starter motor and the starter relays. and all your fuses and stuff like that, here besides the one that's, you know, just inside the driver's side door panel, you want to check all those fuses, so if you check those things, you might find the call and then like I said have your filter checked to make sure there is nodiesel fuel or anything wet where the lines connect like here and you know, make sure there are no areas where you find wet diesel fuel if you're pushing the priming pump. which is right here and you see fuel coming out somewhere at the bottom, then you know there's a problem, but you know these are all the components that we talked about before and they're located right here and the engine and then Actually, this it's pretty easy because there's just two hose clamps here that you can take off and then if you go down the side, you take off the inner fender protection and you can get to the filter very easily down here, um, and then you can check it for leaks. there so this is also the easiest way to put the filter back in so I hope this helps you know what to look for if your truck starts but doesn't continue to run so hey thanks for watching my videos again I hope If this helped you, it is a common problem you will encounter with Duramax trucks, eventually you will end up changing the primer, the primer pump with the rebuild kit, or you will have some problems. with air getting into the fuel system and your truck will stall or not start in hot or cold weather or something so think about that a little bit, hopefully that has helped you, hopefully you can solve the problem and I.

I am going to solve this problem so keep watching my videos, subscribe to my channel and share these things so that other people also know the problems. Thanks again.