runs rich and rough (2 Viewers)

[Seth S]

You have something seriously wrong if you are using that much fuel. I'm honestly not even sure how your truck is starting.

Sounds like your situation is a lot more than just rough running when cold. I think its time for a full baseline check of the engine....fuel pressure, vacuum, compression, valve clearance etc. If you know that mechanically the engine is trim and in spec then its a lot easier to go to the next step. 1/4 tank of fuel in 20 miles sounds like the EFI is at full injector duty cycle and you should be seeing a black cloud behind you. Your cats are likely toast by now if they are still on the truck.

 

[Michaelinlv]

You have something seriously wrong if you are using that much fuel. I'm honestly not even sure how your truck is starting.

Sounds like your situation is a lot more than just rough running when cold. I think its time for a full baseline check of the engine....fuel pressure, vacuum, compression, valve clearance etc. If you know that mechanically the engine is trim and in spec then its a lot easier to go to the next step. 1/4 tank of fuel in 20 miles sounds like the EFI is at full injector duty cycle and you should be seeing a black cloud behind you. Your cats are likely toast by now if they are still on the truck.

I cleaned the throttle body and replaced the intake hose from the TBI to the air cleaner . I think it was the TBI cleaning that did the trick. There was enough caked on mess that I'm sure it was keeping the throttle valve partially open.