Throttle % question

[banton]

I was scanning my 97 GTS for a MIL (P0172/175), but also noticed that the TPS % was reading at 17.2 % with just the key turned on and with the pedal at WOT it read about 75%. Is this normal? I guess I was expecting it to read at 0% at idle and ~100% at WOT position? Thanks in advance for your input.

 

[Martin]

That doesn't sound quite right. At idle, the throttle position is open a bit, but I think it's usually in the area of 7% or 8%. Is it idling OK?

At WOT, you should be seeing the reading at around 100%. If it's not, a good check would be to have someone depress the throttle all the way, and see if you can open the throttle a bit more at the throttle bodies. There were a bunch of '96/'97 cars that couldn't get to WOT because the throttle cable was either not adjusted correctly from the factory, or it was a little too long. My car, for example, has a cable that's probably 5mm too long and I had to remove one of the throttle cable adjustment screws to get the car to go to WOT.

 

[Bluvenm97]

What type of scanner / monitor would I need to check the TPS sensor output?? Sounds intriguing...

 

[banton]

I am going to pull the smooth tubes and visually check the thottle bodies and also double check that the percentage the scanner is giving me isn't actually a conversion of voltage the TPS is seeing (e.g. 17% of 5 = .86).

By the way, I am using an Actron CP9180. It is nice and user friendly for people like me.

 

[Jack B]

I am going to pull the smooth tubes and visually check the thottle bodies and also double check that the percentage the scanner is giving me isn't actually a conversion of voltage the TPS is seeing (e.g. 17% of 5 = .86).

By the way, I am using an Actron CP9180. It is nice and user friendly for people like me.

The TPS is a relative reading and at 100% throttle you will show approximately 81% on a scanner. With a logging software you can use an offset so that the log shows 100%