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The only thing I am expecting for free is some advice which I've had no problem giving and getting for over 15 years on other forum sites. For those that think I'm asking too much, keep walking.
What I am specifically asking about is if someone has had the TPS signal fall into the narrow range that mine is showing and is this an indication of a bad TPS sensor? I have narrowed it down to the sensor or the TCI unit...
I am in Mobile AL near downtown. Thank you to those who don't mind helping others.
Exactly what more are you looking to get out of this post?
If it is narrowed down to either a sensor or controller in your eyes...change the sensor...change the controller...or check the wiring and be sure that's not the issue somewhere between the sensor and controller.
What more can we do for you here on the world wide web?
Specific questions:
Does the fact that my pedal has a narrow range of voltage (2.1 to 4.0) creating the issue with the TPS signal?
Is the TCU having trouble reading the signal because it is faulty or because it is not able to interpret?
Should I get a different pedal?
Should I get a drive by cable throttle body to eliminate the issue?
I was just hoping someone has done this before...
When I bought the TCU I figured it was a popular unit that many have used.....
Thanks,
Last edited by Bondora68; Sep 20, 2023 at 08:03 AM.
Narrow range on the pedal hmm can you Adjust to get a 0 reading? Basically, can you adjust to 0 and get a 0.0 to 2.1 of so then yes you need a different pedal configuration. And if so that should yeild early shifts. The 0.0 reading could be some default reading the controller does when it sees the RPM not jiving with the TPS position but again I dont know enough about the controller to say.
Me I would try and see if i could ajust so the TCM sees a 0-throttle position at 0 throttle then see what happens.
Whenever you are dealing with a nonstock applications and issues many times takes some good ole experimentation to figure out how to best solve the issue, another experiment would be to remove the TPS and manually do the sweep. can you get the full voltage range then?
__________________ Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
Narrow range on the pedal hmm can you Adjust to get a 0 reading? Basically, can you adjust to 0 and get a 0.0 to 2.1 of so then yes you need a different pedal configuration. And if so that should yeild early shifts. The 0.0 reading could be some default reading the controller does when it sees the RPM not jiving with the TPS position but again I dont know enough about the controller to say.
Me I would try and see if i could ajust so the TCM sees a 0-throttle position at 0 throttle then see what happens.
Whenever you are dealing with a nonstock applications and issues many times takes some good ole experimentation to figure out how to best solve the issue, another experiment would be to remove the TPS and manually do the sweep. can you get the full voltage range then?
Thank you for the help!
I ordered a new GM pedal with 6 pin connector...hopefully this will yield better results..
Now I'm confused. Isn't the pedal connected to the engine's ECU?
The ECU would report errors (or limp mode) if the pedal voltages are out of range or different between the two potentiometers.
Good point...So I would need to find a way for my Corvette pedal to have a better range right? Replacing the pedal would not help I guess. Problem is, I do not know how to adjust the pedal...
Due to a custom swap I did, I learned more about pedals and the TAC than I ever wanted to know. But maybe I can use that knowledge to help you.
Your pedal is connected to the "TAC" module which is then connected to the PCM.
Not sure, but I suspect that if your pedal's output is only ranging from 2V to 4V, the PCM would throw codes and go into limp mode.
There are 2 and 3 potentiometer pedals.
It would help me to know the part number on the pedal. And on the TAC module if that is reachable.
Then tell me which wire you connected the TCU to. Pin number and color. (I assume you connected to one of the pedal wires and not a wire going from the TAC to the PCM. Sorry if that is a stupid/insulting question, but I knew nothing this before my swap project.)
The Compatibility between these different components gets very complicated and have seen many "Try" to create a spreadsheet:
-PCM/ ECM + TCM.
-Pedal Assembly.
-Throttle-Body Assembly.
-TACM (Throttle Actuator "Drive by Wire" Control Module).
-EBTCM (Electronic Brake and Traction Control Module).
However few have been successful in doing so...
I feel in part due to Software but also the fact that these Systems were never intended to be used as a stand alone and mixed and matched.
They were designed for specific Vehicles with further Computer Module Integration (TCSCM, BCM, VCIM, Etc...
Sorry for the delay, I took these pics that show the pedal, part number, and which pin I am connecting to. I am connecting to the (aftermarket) harness that comes out of the TAC box and goes into the pedal. It is the yellow wire in the picture. This corresponds to the pin on the top right if you are looking into the pedal connector.
Due to a custom swap I did, I learned more about pedals and the TAC than I ever wanted to know. But maybe I can use that knowledge to help you.
Your pedal is connected to the "TAC" module which is then connected to the PCM.
Not sure, but I suspect that if your pedal's output is only ranging from 2V to 4V, the PCM would throw codes and go into limp mode.
There are 2 and 3 potentiometer pedals.
It would help me to know the part number on the pedal. And on the TAC module if that is reachable.
Then tell me which wire you connected the TCU to. Pin number and color. (I assume you connected to one of the pedal wires and not a wire going from the TAC to the PCM. Sorry if that is a stupid/insulting question, but I knew nothing this before my swap project.)
I'm connected to the pedal using the aftermarket harness coming from the TAC box. I provided the pedal with part number above...
