2G TPS Issue

[Jst4Cyl]

I have searched through threads that seemed close to my topic and I think my problem is elsewhere but thought I would give this a shot.

With that said and out of the way my TPS is reading 14.8%-15.2% at closed throttle.

I have checked to make sure it is closing and it checked out ok, proper slack in the throttle cable. I noticed this after an injector install so I'm unsure of what it could be. It still is plugged in with the clip around it, no broken or corroded wire to be seen. The closed throttle sensor (firewall side of TB) is being pressed in also.

Is it possible that it just went out and is just a pure coincidence to the injector install?

Any info is appreciated and most mods are up to date

 

[Big Woo]

At idle the tps should <5%.

Did you pull the throttle body elbow to verify that the throttle was closing all the way, sometime the cable will start to fray and hang up the full return of the cable.

You may also want to check the wiring and make sure all lines are properly isolated.

Next you might try a differnt TPS sensor, to see if that changes the readings. I would suggest running through the TPS circuit test in the manual this may help you verify whether the sensor is good or not.

Do you have a AFC or something like that in the car? If so verify that it's throttle signal wire is connected well and to the correct pin on the ECU.

 

[Jst4Cyl]

At idle the tps should <5%.

1)Did you pull the throttle body elbow to verify that the throttle was closing all the way, sometime the cable will start to fray and hang up the full return of the cable.

2)You may also want to check the wiring and make sure all lines are properly isolated.

3)Next you might try a differnt TPS sensor, to see if that changes the readings. I would suggest running through the TPS circuit test in the manual this may help you verify whether the sensor is good or not.

4)Do you have a AFC or something like that in the car? If so verify that it's throttle signal wire is connected well and to the correct pin on the ECU.

Responses:

1) I didn't pull the TB but as posted I tried rotating the TB to see if it would close by hand and it didnt close anymore.

2) Didn't see anything that seemed to have any issues (said this in OP)

3) I believe I'm gonna swap another TPS in this weekend and see whats up.

4) I do have a NEO and which this is what I also verified the issue with. Also my stutterbox isn't adjusting right so this further clarifys that it isn't an issue with the wiring on the AFC but a sensor reading issue/wiring prob. Correct?

Thanks for the help anyone else have any input?

 

[brthmltn]

Are you testing it with a battery outside of the cars electrical system? What problems are you having from the readings being off? I had a problem with their are 2 plugs that are the same make sure its plugged into the one closest to the fire wall I believe. Hope it helps.

 

[Jst4Cyl]

1) Are you testing it with a battery outside of the cars electrical system?

2) What problems are you having from the readings being off?

I had a problem with their are 2 plugs that are the same make sure its plugged into the one closest to the fire wall I believe. Hope it helps.

Response to questions:

1) Haven't used an Ohm. meter yet.

2) As in the OP, the lowest reading I seem to be getting is 14.4% this is verified by my datalogger and the NEO. It sits at 14.8% and will sometimes jump to 15.2% . The TB is closing all the way. So this takes a cable issue,sticking TB, and gas pedal issue out of the picture.

I have tested the closed throttle sensor and it is grounding as it should. So I assume this only leaves the TPS, TPS wiring, ECU to be at fault correct?

As I said in the OP, I discovered this problem after installing new injectors. I had a buddy "jiggle" the wiring around while I watched for changes. But nothing changed. None of the wires seemed to be damaged and the clip on the TPS seemed to be fine. I unplugged the TPS and of course it read 0% but I still couldn't adjust the stutterbox like I was able to. By me saying that "I couldn't adjust the stutterbox" I mean that it didn't adjust from the -14,-7,0,7,14 instead it was like those points on the boost gauge was off. This is what worries me that it might be my ECU.

BTW, the ECU has new caps in it and was fine previously.

Thanks guys

 

[steve]

At idle the tps should <5%.

No on a 1G it should read about 10% or 0.5v when the throttle is closed.

Unless you measure in the sensor voltage going into the TPS, the total resistance of the TPS and calculate the correct value for a voltage divider with those parameters to give an output of 0.5v you can't set the TPS by resistance no matter what the VFAQ says.

There is too much variation in production parts for one size fits all answer.

 

[Jst4Cyl]

Well, just so everyone can rest since SO, SO, MANY people jumped in to help with the issue I thought I would give an update over the problem for future members trouble shooting.

I traced down all the wiring and couldn't find any issues with the wires, voltage seemed correct, no obivous problems. So I kinda gave up on it and threw the battery on charge because the voltage had fallen a little and I didn't want to drain it all the way down (the car has been sitting for awhile )

So, a few day later I went over to my dads house to pull the charger off and I thought I'd check the voltage on the NEO and for $hits and giggless I tried the stutterbox and I be damned if it didn't work just fine So voltage must have been the issue because the NEO is reading the same voltage (under sensor check: Which was .47 volts)

So hopefully this is the end of it but I doubt it is. I will give it awhile and report back if it changes.