hi, I just recently bought a 99 psd 6sp and put on a 5 in exhaust. I have been traveling the past couple days and this problem is getting worse. I can only seem to get the truck up to 65 maybe 70 or just around 2000 rpms, and there is just no throttle response after that. I can push the pedal to the floor and nothing seems to happen. And any little hill will drop the speed to 55 or 60. The engine sounds fine and I can hear the turbo working. also, in lower gears, the engine wont rev past around 2400 before making a loud deep popping sound. Any help would be appreciated

thanks

Mike

 

I would get it scanned to see if there are any codes stored. If it runs that bad I would be surprised if there were no codes stored.
That said I would like to venture a guess on a very clogged fuel filter and/or a failing fuel pump causing abnormaly low fuel pressure/supply to the injectors.

 

Here are the codes that were stored:

-Wastegate solenoid circuit malfunction
-PCM Keep Alive Memory Malfunction
-Turbo/Super Boost Pressure Low
-Turbo/Super Boost Pressure No Flow Detected

 

I changed the fuel filter, but the problem isn't much better. Oh yeah, the truck is a 99, not a 99.5. I read that the pump changed for 99.5. I guess i'll have to take it somewhere to have it looked at.

 

Hmmm, the spring give up in your wastegate control valve? No spring pressure to hold the wastegate shut would make three of those codes.

 

Thanks for the reply, I'll look into the wastegate spring...Just an update, the problem isn't bad at all when the truck is just warming up. I can easily get up to 80, though can't really go faster than that, and I am able to rev higher in each gear. After driving a while, top speed reduces to maybe 70, and its like there's a rev limiter at ~2300 rpms.

thanks again,

Mike

 

I was gonna take the truck into the dealership last night, but it wouldn't start. It would turn over, but no fire....so, it had to be towed into the dealership. Still waiting to hear back what they find