TPS closed voltage discrepancy between warm and cold ECT

[jdniss]

Hi,

Discovered an issue with TPS 0% voltage values between cold and warm ECT,
where the TPS closed voltage degrades away as ECT rises.

Seeing about 0.50v at closed "0%" TPS during warmup,


Then 0.37v at 0% closed TPS by about 75~80deg ECT

If I calibrate the TPS while the car is stone cold - once warm ECT is reached, the TPS is doughy along with overrun fuel cut's ability to switch off while on partial throttle.

Then vice versa for warm ECT - if I recalibrate TPS when the car is warm, cold ECT startup TPS response is subsequently affected and reports 3~5% while closed - idle speed control unavailable, etc

I've looked around the forum, can't find anything that really explains the issue..
 

I figured maybe the TPS sensor was on it's way out - but the reported values are consistent between cycles.
Apparently the factory ECU (S15 SR20) sets an idle flag anywhere between 0.35~0.65v with TPS closed.

Thanks

[Adamw]

Assuming you do have free play in the cable and the blade is not sticking then it would most likely be a worn sensor or bad ground/ground offset.