Engine Stuck At Idle

[pako2010]

I'm writing from France about a problem with our 1999 IS 200, manual transmission, 110k km (about 70k miles). The other morning the engine got stuck at idle -- depressing the accelerator didn't change the engine speed at all, and the check engine light came on. The car had been parked indoors and the problem came up within a few blocks of leaving the garage, with the engine just warming up. We parked the car and came back the next morning and the engine seemed to respond normally, but we didn't really drive it. We had the car towed to the local Lexus dealership, which wants to replace the clutch. This doesn't make a great deal of sense to me. Any ideas?

[1990LS400]

It sounds like a defective Throttle Position Sensor (TPS) or Pedal Position Sensor (PPS). I had a similar problem with a non-responsive accellerator pedal on a 2000 LS400. Pressing the pedal did nothing and the Check Engine Light came on. I had both the TPS and PPS replaced - one had failed and the other tested below the acceptable range.

The dealership should have instructions on how to test the TPS and PPS.

[IanH]

I'm writing from France about a problem with our 1999 IS 200, manual transmission, 110k km (about 70k miles). The other morning the engine got stuck at idle -- depressing the accelerator didn't change the engine speed at all, and the check engine light came on. The car had been parked indoors and the problem came up within a few blocks of leaving the garage, with the engine just warming up. We parked the car and came back the next morning and the engine seemed to respond normally, but we didn't really drive it. We had the car towed to the local Lexus dealership, which wants to replace the clutch. This doesn't make a great deal of sense to me. Any ideas?

^X2

certainly isnt the clutch !!!

[pako2010]

Thanks to both of you. The TPS and PPS sound like promising leads, and I've since learned that the "stuck in idle" is probably just the car switching to "limp home mode", which could have been triggered by either a TPS or PPS problem, or maybe something else. In any event, we'll have a well-informed chat tomorrow with the Lexus service manager, who was away last week when one of his wizards proposed replacing the clutch.

[IanH]

If its a TPS problem ( and Probably PPS) it should throw a code. Did you ask them if there were any codes ?