I have a 2002 gmc with a duramax diesel engine. It starts every morning, but after it warms up and i shut it off, if i start it immediatly it will start. If i wait for 30 minutes it will not start. If i leave it for 2 or3 hours it will start again. The check engine light dosen't come on so it shows no codes. I took it to a gm dealer and they said it looks like the injector pump may be the problem. I took it to another dealer that works with diesels, they ran all the tests and put a new hose from fuel filter to injector pump. The truck worked the same as before. I took it back and they did all the tests and put a new injector pump on .The truck started at the dealers but when i got home and let it set for 30 minutes it would not start. after 3 hrs it starts . It always takes longer to start than normal when it does start. The dealer says the injectors test ok. My question is could it be the injectors? why would it start when cold but not when warm?

try another dealer

Mine is doing the same exact thing, it gos in for injectors tommorow so i will let u know what they find out. pm me and remind me to post in case i forget cause mine is exact thing urs is doin.

I would like to hear the outcome of this. what the fuel prime look like when you wait 30 mins? but that cant be it.

I took truck back to dealer and they ran the injector tests again.They said the injectors passed the test,and won't be replaced under gm's campain.I guess my option is to take it home and buy a truck'and it won't have a duromax engine in it.It is quite a bummer after spending $3000. on it and it is the same as when i took it in.

I am about done with GM Duramax. I have bad injectors (low power, bad smoke at idle) and warranty denied at 3 dealers.

But all say... Pay us $ 5K and we'll fix your problem by installing injectors but it ain't covered under warranty.

I am going to trade for a Ford F250 with a Triton V-10 and get away from this money pit.