My 2500HD started smoking white smoke at weird times about 6 months ago. I had the injectors replaced about 20,000 miles ago. When I start it cold it doesn't smoke a drop, but after it warms up it will start to smoke on and off, mostly I notice it if Im on side streets have to stop a lot at signals, when Im on the freeway at higher RPMs it seems to clear up. But other times it runs clean in side streets and smokes on the freeway. I dont think its an injector issue because it isn't consistant and never smokes cold. I noticed recently that the turbo doesn't seem to be spinning when it smoke really bad, even at high rpm, but im not sure on that. When I hook it up to a computer I dont get any injector errors, the only error I get is for a glow plug malfunction which to me would make it smoke on startup not after it warms up. I dont know if anyone else has this problem but any help would be really appreciated.
2003 GMC Sierra 2500hd Diesel white smoke
- Thread starter adam4d
- Start date
Molson02536
New member
Shooting in the dark, but have you check to see if your EGR cooler has a small leak??? Sounds like every time your EGR activates, the coolant leaking from your EGR cooler is going through your intake and out your exhaust. Thats why its not a constant amount of smoke coming out your exhaust pipe.
Start with that and keep us posted.
Molson02536
Last edited:
Thank for the suggestion. I did a bit of research and i guess if the inside of the EGR cooler is gummy thats a sign of a leak? Ill try pulling it tomorrow to see if thats the case. Just a quick note, when the truck is smoking it has a very strong burnt diesel smell, if it was coolant getting into the exhaust would it smell like diesel?
Typically white smoke tends to be more of a coolant or water issue not fuel or oil. Fuel or oil would be more of a blue or black smoke. Also when it is cold you can check the tailpipe. Sometimes if there is unburned fuel or oil (blow by) the tailpipe can be somewhat tacky to the touch. I have had other diesel vehicles that we have had issues with the EGR Valve (as mentioned above) and that could be a good step to check. Good luck!