Throttle Position Sensor GRRRRR

[SweetChuck]

Out of the blue my car starts throwing code 7 ECL only when WOT . Code means Throttle angle , so I change out the sensor and proceed to set up the position , the lowest extreme all I could get was 800mV instead of 500mV, so I put the other sensor back in and same deal . You have to turn the sensor fully clockwise to get this voltage , the other extreme is 1.6 volts .
At WOT it measures 4.8volts not 4.5V at the ecu . I changed out the ECU to no avail . I double checked that the sensor was on the throttle correctly and that the butterfly was fully closed .

I am out of ideas

 

[Daedalus]

Silly thought--how accurate is the voltmeter? Did you test the output voltage from the ECU to verify it is 5.00V?

 

[SweetChuck]

Silly thought--how accurate is the voltmeter? Did you test the output voltage from the ECU to verify it is 5.00V?

Not a silly thought , voltmeter is Fluke 100% acurate , did some more tests though and the voltage to the unit is 7 volts , but with both ECU's , so the plot thickens .

 

[DutchBlackNsx]

Have you measured to the zero potential. Also make sure that your engine has a no floating potential. Do this by measuring from a good groundpoint to the engine, resulting in 0 volts.
Check ground wiring to your engine.

Just a longshot, since you tried a lot allready.

 

[SweetChuck]

There seems to be no ground problems anywhere , but it seems like there is 400 mV leaking in there from somewhere with the ignition off . This voltage lurks until I pull one of the green main harness connectors near the firewall .
This is totally annoying .

 

[Daedalus]

You have my sincerest sympathy. Troubleshooting electricals isn't one of my favorites. When I said check for 5.0V I was assuming that's what it needed, but double-check with the FSM if you haven't already. Hope you nail it soon.

 

[Larry Bastanza]

Where are your ground straps - Engine to Body?

In the early cars they moved around a bit.

Regards,
LarryB

 

[SweetChuck]

I found the problem . The old AT trans unit which I left in , had not posed a problem since it lays dormant , developed a fault and started sending things haywire , even the TCS error started coming and also effected performance . I suppose due to the TP sensor reading wrong feedback . I disconnected it and everything came good :smile: :smile: but only after I went through everything else first ,thats always how it goes though

I really do need to change the interior harness to a MT version to make the conversion fully complete , too expensive for what its worth though .