2003 Tahoe P1516 Code

[viperbluelx]

Alright, I bought my wife and 03 5.3 Tahoe a little over a year ago. I've made a thread about this in the past, but I thought I'd start fresh.

 

Soon after buying it, it through a P1516 code and went into Reduced Power Mode. You could turn the key off, let it sit around 1 minute then it would fire up and be fine. It might be good for a day, it might be good for a month.

 

The next time it did it I bought a new throttle body for it(probably the wrong move), and it was find for several weeks then it sprung up again with the P1516.

 

Next I swapped the stock pedal position sensor for a new dorman sensor.

 

It started the P1516 again so I dropped it off at the local chevy dealer. They said that it just needed to be flashed with the latest ECM revision and they said they "calibrated" the throttle body with the other sensors.

 

Ran fine for about a week and then on cold starts it would idle rough and surge at part throttle and throw a P1025 code....(pedal position sensor).

 

Luckily I kept the stock GM pedal position sensor since I wasn't even sure it was bad, I swapped it back on and we drove the thing everywhere for the past 2 weeks and now it's started throwing the old P1516 code again but the P1025 is gone.

 

I know this is a long read, but the problem is so intermittent that I can't trace anything down anywhere and I have no idea what to do now. The dealership said they did all they knew to do, other than I guess throwing new parts at it??

 

Any ideas?

 

thanks in advance,

 

Mark