Tps in but wont adjust... Help please!

[90gen1tsi]

So here is my results. My car is a 90 tsi

Ground (Black wire) to Green with white stripe = 2.4v-2.6v depending on where tps is positioned.

Black to Green with red stripe = 4.9v no change with tps adjustment

Green with black stripe =0.1v with no change when tps is adjusted

I have no idea where to go from here.

 

[Absit]

Have you considered using the VFAQ method, maybe verify the TPS isn't bad?

 

[90gen1tsi]

vfaq does not match up to my car... I wish it did. I bought this TPS from graveyard and he said it tested good.

 

[90gen1tsi]

Can some one please chime in here!! I am at a loss... My chiltons says nothing about this and I have no idea where to go from here!

 

[steve]

The 90 FSM says the TPS uses three wires from the four connector plug:

Pin 2 Green/Black Sensor Ground ECU pin 24
Pin 3 Green/Red Sensor Power ECU pin 23
Pin 4 Green/White TPS output ECU pin 19

Measuring voltage between the Green/Black to the Green/Red should read 5v.
Measuring voltage between the Green/Black to the Green/White should vary by position from close to 0 to 5v. On the car with the throttle closed it should measure 0.48v to 0.52v id the TPS is adjusted correctly.
Measuring the resistance between the Green/Black to the Green/Red with the TPS disconnected should read between 3.5k and 6.5k ohms

Pin 1 Green goes to the IPS switch.

 

[90gen1tsi]

Thank you so much for that information! That's exactly what I have been looking for! I am assuming FSM is some type of service manual, where do you find this? So I know where to look for this type of information.

 

[steve]

Factory Service Manual
eBay at this point it the best bet. 90's are unique and you need the real paper books for that year. The CD with scans of the manuals don't have the 90 specific information.

 

[90gen1tsi]

Thank you again! I have had a heck of a time finding the right information for my car... The chiltons is ok on some areas but like you said the 90's are unique...

Ok so testing per above I am still getting between 2.4 to 2.6 volts when testing Green/Black to Green/white. Would that be looking like bad ecu or a bad tps?

 

[steve]

I am not having any luck with this dang thing... Testing between G/B and G/W I am getting 2.4 to 2.6 volts... Would that point to bad ECU or another bad TPS?

What sort of voltage are you seeing on the car side of those pins with the TPS disconnected?
Have you taken the TPS off the throttle body and made sure the inner coupler is moving? Any change in voltage when you turn the coupler my hand?
Did you check the resistance across the Green/Black to the Green/Red? How about between the Green/Black to the Green/White while you move the coupler?

 

[90gen1tsi]

I did take the tps off the throttle body and make sure the coupler was moving freely. I did not test it while off though. I have not tested the resistance on this TPS. I bought it from graveyard and they assured me it was tested and good. I will pull it tomorrow and test voltage and resistance with it off the throttle body. I checked the car side a couple weeks ago and don't remember the results, but that was before I had been able to get the needed information that you provided me so that I will test again tomorrow also.
Do you know what the numbers should look like on the car side of the plug?
The G/B to G/R was good at 5v though

Thanks again for the help! Just some direction as to what I am supposed to be checking is great! I hate chasing electrical stuff... Mechanical stuff I am much better with . I am sure thats the norm though.

 

[steve]

Off hand I don't think you should see any voltage between G/B and G/W with the TPS disconnected when checking the car side. If you do have a voltage there it might be why the TPS isn't working right and indicate a wiring or ECU problem.

 

[90gen1tsi]

Sorry its taken me so long to do this... Life got crazy for a bit there.


Measuring voltage between the Green/Black to the Green/Red should read 5v. 5v
Measuring voltage between the Green/Black to the Green/White should vary by position from close to 0 to 5v.2.4-2.9 (4.6 @wot On the car with the throttle closed it should measure 0.48v to 0.52v id the TPS is adjusted correctly. closed throttle is at2.4 wont go lower
Measuring the resistance between the Green/Black to the Green/Red with the TPS disconnected should read between 3.5k and 6.5k ohms 4.15 ohms

Car side

gb-gr 4.9v
gb-gw 3.8v



Tps tested off the car but plugged in

gb-gw 1.9-4.7v

 

[steve]

I'll have to double check but I still don't think there should be any voltage between gb-gw with the TPS disconnected. That would imply a wiring problem or a ECU problem.

 

[90gen1tsi]

Yup... The wiring is all stock not been messed with so probably pointing to the ECU is my guess... Let me know what you come up with! Thanks again, you have been a life saver!

 

[90gen1tsi]

Any luck confirming the GB to GW voltage problem?

 

[steve]

I haven't been down in the basement to hook up an ECU and check it.

I verified this morning that there isn't any significant voltage between pin 19 (TPS output) and pin 24 (sensor ground) at the ECU when the TPS is disconnected. I saw about 12mV on the meter which has a much higher impedance than the TPS. With the TPS connected it's output voltage should swap any leakage I see with just the meter.

So it sounds like it's time to have someone check your ECU for damage.
I send everyone to ECMTuning now. They are the only place I'd trust with my stuff.

 

[90gen1tsi]

Sweet I will have to check them out! Thanks buddy!

 

[90gen1tsi]

Ok Steve here I go again! Got an ecu from a guy in the area. plugged it in and the tps adjusted like it was supposed to! Ya!! So I start the car and try to go for a drive... the car cuts out any time I try to give it gas now. So I swapped in the old ecu again so the car is at least drivable.

one question I had is would this happen if it was the wrong ecu? The kid said it came out of a 90. but I can't find the number on the 1g part numbers on vfaq. it is md166255

Any other ideas?

I just found one of your answers on that number being a non turbo ecu... That bites! Guess I am F'ed
looking at the board inside the housing. Is there any way to tell if it matches the housing? He says it came out of his 90 tsi. I was wondering if maybe someone had changed the board? Why would it work in his car and not mine? The number on the board is je331b997a I will google this too and see if I come up with anything.

Well from what I can tell it is the board from the original...

 

[steve]

Eclipse Talon Laser Galant 3000GT Stealth ECU ID Reference

As you have discovered not only is it not a turbo ECU but it's not for a 90 either.

Each model has a part number and a unique E2T number. The circuit boards have the last four digits on the E2T number printed on the white edge connector. So in this case a board from a MD166255 will have 6572 with a letter at the end printed on the connector.

 

[90gen1tsi]

Yup! Your chart is very useful! I have been referring to it all evening. I will be sure to use it in my quest for a good ecu. My car is my daily so I don't have time to send it off to be fixed.