So I've been chasing this idle issue and narrowed it down to my TPS. I've got a cam in my car and the tuning is dialed perfect, PatG took care of it. I've opened up the TPS holes, reclocked, it's 0.50v when the throttle is closed, and done probably 20 relearn procedures. Every time I key on, the TPS is at 2.0% and making the idle suck. The only time I can get the TPS to 0.0%-0.4% is when I flash a new tune. If I hit the key after flashing, it fires up, AC on and in gear, idles perfect. If I cycle the key, TPS is back at 2.0% and it won't idle right.

The 5v reference on the sensor is at 4.95v and the ground ohms to zero anywhere on the block. I'm going crazy trying to chase this issue. WOT always shows 100% as it should. I cannot figure out why the car wants TPS to be 2% every time I cycle the key! Any help is greatly appreciated!

 

Throttle cable too tight?
Do the volts return to .500v

 

I did solve this issue. I used a pink wire for my wideband, dumb decision. When the O2 heater kicked on, it caused a voltage dip going to the PCM and when the heater turned off, voltage came back up which the PCM detected as me rolling on the throttle slightly. Added a relay like I should have in the first place and all is gravy now!

 

Good find!

 

That is a good find and follow up.