TPS Voltage goes down

[FIS]

Just installed Storm in Corolla AE111 with 4ag20v engine and I have issues with TPS voltage as following, I adjust TPS at throttle position close to 0.71V then doing TPS setup to get 0 to 100% position in the PCLink software, when engine run the TPS voltage dropped to 0.5V which makes engine rough when accelerated. Then I tested by readjust TPS position back to 0.71V while engine run, the engine accelerate smoothly, with this position when engine off the TPS voltage become 0.89V (5.7%). The battery input and 5V output voltages are normal in Runtime Values.

[Adamw]

My logic would say there are 2 possibilities:

1. Maybe the TP Sensor is damaged and gives a different resistance when there is engine vibration present.
2. You have some wiring issue where there is something messing with the ECU 5V or ground reference when the engine is running.  I think you would see it in the runtimes if the 5V was effected, so maybe more likely the ground.

 

 

[FIS]

6 hours ago, Adamw said:

My logic would say there are 2 possibilities:

1. Maybe the TP Sensor is damaged and gives a different resistance when there is engine vibration present.
2. You have some wiring issue where there is something messing with the ECU 5V or ground reference when the engine is running.  I think you would see it in the runtimes if the 5V was effected, so maybe more likely the ground.

 

 

I just changed TPS with new one, clean up the body and engine ground points detached MAP, IAT, ETC sensors, IAC,  reseat ecu connectors but problem still there. Then came up with idea to move TPS input from AnVolt 1 to AnVolt2 ....problem disapeared!!

[FIS]

I was wrong...the problem still exist !!

[FIS]

Found the culprit !! it was engine vacuum sucked ITB butterflies causing TPS moves close