mayad79

Hey folks,

Just got my car back and the throttle @ idle is almost 2K. If I turn the key to power w/o ignition and press the pedal to the floor, then start the car the idle is still 1500 rpm, the car is warm.

The question I have is the throttle adjustable, such as a cable that can be tightened or lossened?


Thanks all,

Och

iTrader: (3)

First of all, what year is your car? 1998-00 have throttle cable, 01+ has throttle by wire.

Either way, both have TPS sensor, which usually lasts no more than 120k miles.

mayad79

Sorry,

The car is a 1998 GS400 with 207,000 miles.

Och

iTrader: (3)

Try adjusting the cable, and if that doesnt help, replaced TPS sensor. These are the two most likely reasons for high idle.

SLAMDGS4

iTrader: (1)

adjust the throttle cable..you have to take the engine cover off then you'll have access to the cable..if that does not work check for a vaccum leak before replacing the TPS

JeffTsai

iTrader: (1)

There's no reason that sensor should go out unless it recieved some kind of shock/damage. Think of it, how many Toyotas are still out and about today since the early 90's or late 80's. Most of those are still running on the original TPS they came with from the factory.

As for mayad79's problem. There's an error in your electronic throttle control system. It sounds like the ETCS on your car is malfunctioning (failsafe mode: you can't rev past 2000-2500rpm or so). Hook up an OBD2 scanner to figure out which sensor malfunctioned. There are 2 sensors and 1 control motor. One is the Accelerator Pedal Position Sensor, the other is the Throttle Position Sensor, and there's the Throttle Actuator Motor.

Och

iTrader: (3)

Thats true to a point, but also the TPS fails on a lot of cars at around 150k miles. Its true not just for Toyotas, but practially for any car on the road that utilizes the TPS. The TPS is basically a spring loaded resistor mechanism, and the mechanism wears out, the contacts fail over time, etc. In my old GS300 for example it failed at 130k and triggered a CEL. In my GS430 it didn't fail, but I replaced it when I replaced my spark plugs and cleaned TB.


He doesn't have electronic throttle system, 98 still utilized throttle cable.

JeffTsai

iTrader: (1)

All the 2GS uses a electronic throttle system. The main difference between the 98-00 and 01-05 is that the Gs430 completely eliminated the throttle cable. The GS400 still utilizes an electronic throttle system, but the actuator motor and pedal position sensor are actually located on the throttle body. The GS300 is also setup the same way and the design did not change from 98-05. The cable's main purpose is for backup in case the pedal position sensor fails, you can still pull open the throttle by cable and limp the car into a parking lot or gas station. On the GS430, if the APS sensor goes out then you are crap out of luck since there is no cable backup lol.

mayad79

Does anyone have a picture of what I should be adjusting. I have been searching but have not found any.

BTW, there are no codes, no lights either. I have replaced the Accelerator Pedal Sensor.

Thanks all,

mayad79

Well,

I took the engine cover off and found the adjustable cable.I used two wrenches to adjust, and the car on to check rpm.

I made a little change ad the rpm's are 1300 cold and 800 warm.




thanks,