I dont like doing this, relaying information about an issue that I have not witnessed, but here goes. My dad has the aforementioned truck and called me this afternoon to describe an issue. He states that he took off from a stop and everything was fine but when the trans shifted to 2nd he lost power. I asked if it died or if it just didnt have any power, he said no power, pedal to floor, nothing. I asked if it had rpms but just doenst "go", and he said that the tach showed 3000 rpms but the engine was quiet and that it definitely was not turning those types of rpms, that it had no power. But after a while it slowly built up power/speed, shifted to 3rd and everything was fine after that. This was from a cold start after sitting all day in parking lot.

Last few weeks he has been complaining of low power at startup when cold, but after it warms up its fine. He has mentioned that pedal is to the floor but nothing happens. I thought it was TPS at first and suggested cleaning contacts. But again, I have not witnessed this, going off of his descriptions, which seem inconsistent at times. Not sure what is going on without actually experiencing it myself. Im still thinking maybe its the TPS but im wondering if maybe it could also be the tuner/pcm going south. It has a Banks tuner that was already installed when he bought the truck and has an Edge digital monitor. I do not know what any of his gauges were reading at this time, thinking maybe that it could be a leaking boot if happening at full throttle from a stop, builds boost, leaks and looses power, but then reseals and everything is fine?

Ive tried telling him to take it easy on cold startups as my truck exhibits funny behaviors if i just jump in it cold and take off. But it seems to be falling on deaf ears. But this is south LA so cold is not really cold as compared to some of you folks. Anyone have any thoughts as to what is going on? I may give him BTS's number and have him call it looks like it may be a trans issues. What are the symptoms of a failing mechanical diode in the trans for reference? Any info is appreciated.

 

It's not a trans issue. It's an engine issue.

 

Thanks Mark. Had to ask, the way he described it he was thinking it was the trans. Glad to rule that out. Anyone have any ideas of where to look next?