my trucks got the winter blues

[dropped93]

so my truck likes to act up like this morning, when its pretty cold outside. got the 350 all stock except headers and full exhaust. this mornin when i walked outside and started my truck, it was runnin like ****, like half the cylinders were missing. and then the check gauges light came on. its got me pretty stumped because the only light i ever get on the dash is the check gauges light, when its cold outside. anybody able to shed some insight on this??

 

[Badass69]

Does the service engine soon light ever turn on, even if you just turn the key on but have the engine off. Does the paperclip trick reveal any codes or is the truck simply just code 12. It could be a ton of things really at this point. EGR sticking open ( creating a massive vacuum leak at idle, it will run awful), igntion problem, fuel pump on it's way out.

 

[RHamill]

EGR sticking is what is sounds like, they get gummed up quite a bit on these 350s, I'd let it run for a while until it's warm, then rev it up to force exhaust out and try to unstick that EGR. Or put it to the floor while cruising somewhere safe. Could be any vacuum leak really.

Maybe a plugged Cat, if you have them.

 

[dropped93]

okay, and no cats, its headers into straight dual into cherry bombs

 

[miles5241]

my truck does the same thing. super ruff idle, sounds like its missing no engine light but once it warms up everything is fine. tranny shifts goofier sometimes in the cold too. but -10 degrees will do that

 

[Badass69]

EGR is really simple to check out. It's just on the passenger side of the intake manifold behind the throttle body. 2 nuts hold it down. Pull it off and take a look to see if its a mess or not. Then you can clean it as well. You can check if the pintle moves up and down freely with it in place as well, as a quick check but you won't know if it's seating all the way or not.

 

[RHamill]

If it sounds like a diesel when you start it for the first time in the cold, that's just Piston Slap, all these trucks will do it, goes away in about 10-15 seconds.

 

[Badass69]

If it sounds like a diesel when you start it for the first time in the cold, that's just Piston Slap, all these trucks will do it, goes away in about 10-15 seconds.

The Vortecs... some of them. The TBI trucks still had normal pistons in them so it's not near as common.

 

[RHamill]

The Vortecs... some of them. The TBI trucks still had normal pistons in them so it's not near as common.

Oop, I was looking at your signature thinking it was his truck being a 96, but yes, i've had 2 vortec trucks and my mom has 1, all 3 of theme did/do it every winter when its really cold out.

 

[Badass69]

Oop, I was looking at your signature thinking it was his truck being a 96, but yes, i've had 2 vortec trucks and my mom has 1, all 3 of theme did/do it every winter when its really cold out.

It's all good. Mine is one of those dreaded silent Vortecs. Scary..... GM must have gotten the piston to wall clearance right in mine, lol.