How many of you guys who have experience the rough idle issue with the GS4 changed the TPS and it solved your problem?


Cmon guys, I really need your help cuz no damn dealership I went to could fix my rough idle. I'm really thinking of buying the manual and replace the dang TPS myself it it is the culprit.

 

How many times has the dealership actually changed the TPS?

It is a pretty simple procedure for the dealership. emove the engine cover
Plug in the Lexus scan tool and adjust the TPS.

 

There's no adjustment on the TPS. If you remove the engine cover and look at the throttle body. You will see the throttle cable attachted on the right side of the throttle body and that's Accelerator Pedal Position Sensor. And on the left side(driver side) you will see the TPS. If you look closely, you will not see any slot for the adjustment where the screws bolt on.

 

The APS is not adjustable. THe TPS is adjustable. It is held on with two small phillip screws. If you shine a light on it than you can see the slot where the screw resides . THe whole TPS will rotate about 10 degrees. I have adjusted over 10 GS's. I have adjusted mine over 15 times looking for the right combination of drivability, power, shifting, etc...

 

The adjustment can be done with an Ohm meter if a Lexus scan tool is unavailable.

 

This is a actual GS400 TPS.
Nothing is wrong with it.
Since the TPS is prone to premature failure, I changed it while replacing a defective APS.

 

To think I may have hard a part in starting this poll, LOL j/k!

The TPS made a noticeable differnet in how the engine RPMs moved on my 90LS. I watched the techs that installed it use some kind of ohmmeter to get a resistance number instead of a comuter reading tool. After reading that little diagram I wonder if I should take it to the dealer and make sure it's set right.

It is very sensitive to adjustment and must be set on the dot.

 

Thanks Pearlpower for the info. I was thinking about something else or another TPS from another car.

 

You are welcome. As posted above, the TPS adjustment is very sensitive. In fact, tightening the screws can knock it out of adjustment. If in doubt, take it to the dealer. Sometimes if you have the engine cover off, the tech "may" check/adjust it for free.
Maybe

 

wow, the replies!

anybody here got the specs on how the TPS should be adjusted in terms of the resistance levels between the contacts? if someone has the repair manual, please scan a pic. i'm planning to use a multimeter, so i can't use the instructions pearlpower uploaded, but thanks for helping!

i need something like this:

 

the specs i uploaded is for an old toyota, i think a celica. if somebody has the specs for the GS4, i would really appreciate it. thanks in advance!

 

hi

i recently installed borla tips.. i didn't noticed till now.. but i dont remeber having that time when car shakes a little bit.. but then again... i didn't had it very often with stock tips..

 

LOL!

Alexus - the post is about TPS which stands for throttle position sensor, not TIPS (as in exhaust tips). Tips only won't change anything at all about your GS's performance - your tips are an appearance modification only.

 

hahah) whoooops my bad

 

LOL cracking up