bad idle
 

ok, i have this continuing problem with my car. i have a check engine light and a loopy (500-800 bouncing) idle. the engine code is for the tps (both narrow and full range codes). i have tested the voltage and ohms at idle and WOT. i am still not getting a steady idle and the light is still on. now the strange part. i get a steady idle, if i turn on my headlights. any ideas or suggestions would be much appreciated. car setup in sig.

pic of my car is just a test.

Test your BAC valve. And set your TPS using the two-light bulb method. The multimeter test is inaccurate since the voltage at the ecu is most likely different than the voltage at the connector.

And if you haven't already done so, re-do the grounds.

Good luck

what do i need to check about the BAC valve?

Resistance, whether or not it moves when you apply 12V. etc etc.