Engine/Transmission (1998.5 - 2002) Sick truck

[KcoleKennyc]

Having a problem-truck is sick. I do some hot-shotting and was in another state last Friday. Truck had been running fine all day until I stopped at a light about 200 miles from home. The engine seemed to get louder and lost a lot of power. The cel light never came on and all gauges were normal. It was at a bad time of day with extremely busy traffic and there were not any places to get off the road. When I finally did get off, I shut it down and checked under the hood. The water and oil were full, checked the connections from the turbo and they were ok, I have blown one of those before. The boost pressure was below normal as was the power, I guess it was defueling or in the limp mode. Let it set for a few minutes and tried it again, it started out better but quickly lost power again. Called home to have someone on standby just in case. Continued on in the heavy traffic until I got to where I needed to make a stop. Let it set for about an hour, checked everything again and continued on. There was never any of sign of smoke from the truck, it just didn't have much power. Got on the interstate and headed home, it finally got up to a descent speed so the traffic wouldn't run over us. Drove another 80 miles or so and stopped and let it rest again. I could get up to 65 down hill and a couple of times got down to 35 going uphill. It would probably run faster but I was grossing 16K or so. Got my tuner out the next morning and attempted to check for codes. The power light won't light on the tuner, got another one and it wouldn't light it either. Don't have any power under the dash to the terminal where the tuners plug in. I checked all the fuses hoping that I would find a problem, they were fine. I have all the manuals for the truck but haven't found the one for the engine yet, maybe tomorrow. Just wondering if anyone had ever had such an experience with their truck. I have about 430K on it and it has always brought me home but I had my doubts on that run. My uncle was waiting to come and get me if it quit, couldn't stand the idea of being pulled in by a Chevy wrecker. Would appreciate any info that anyone has about what to check and if I run across anything I will post it on here.

 

[DIESELWRKS]

soon as you can get some codes pulled, I would think maybe dead peddle syndrom, throttle pos sensor, could try and re-calibrate it. or worse the vp is dying.

 

[SSolderitch]

the voltage cc buss from the central timer module behind the dash. It makes 5v on two pins for everything. I would check that? It talks to the abs,transmission - auto, pcm, overhead, air bag, ecm & pcm. & the odb port.