Hello, I have a 1994 GMC Sierra with the 5.7L 350 engine in it. Recently I was having acceleration issues as well as idle issues. Going through diagnostics, I found that it could be attributed to the Throttle position sensor (TPS) so I ordered an A/C Delco replacement. I removed the old sensor, lined the new one up on the slot and installed it without any issues. I then ran the truck and idle seemed fine. I did take it on a drive and found that it was surging and cutting out much worse than before. I figure there may be a relearn procedure on these sensors but I am unsure how to perform that. I have disconnected the battery cable for about 5 minutes and that didnt do anything. I also cycled the engine a few times letting it run for 3 minutes, then shutting it off for about 1 minute, then letting it idle for 3 minutes again. I have looked all around but haven't been able to find any answers for something this old. Any help would be appreciated. Thanks!

 

Here’s the throttle body relearn procedure:

1) Start the engine and let it idle in park for 3 minutes. During that period the idle may be higher idle than normal.
2) After 3 minutes, turn the engine off and leave it off for 60- seconds.
3) Start the engine again and let it idle in park for 3 minutes one more time. During these run periods you may see a check engine light. Scan for codes and if you get throttle body related codes, clear them.
4) If the idle speed is still off, drive the vehicle at speeds above 44-mph and operate several acceleration and deceleration cycles. Then repeat step #3 one last time.