Vsc Off Light Comes On And I Loose All Throttle

[ISRydr]

I have a 99 LS400 and that's been having intermittent issues with the orange VSC Off light coming on at which time I loose all throttle and the idle goes much higher than normal, around 2000rpm. This issue has been going on for over a year now and the frequency is becoming more regular. It happens within the first couple of miles of driving after first starting it from an overnight sit. So far I've been able to pull over, turn it off, then restart at which point I once again have throttle and proper idle rpm but the VSC Off light stays on for several miles then turns itself off. I'm concerned that this will happen and will strand me when I'm out of town and I travel often. I've had it to the Lexus Dealer and my local mechanic but to date nothing has been determined to be wrong. Has anyone else experienced this type of problem? Or does anyone have an idea of where the potential problem might be so that I can at least be aware of how to discuss this with a repair shop in the event I get stranded? Any help would be greatly appreciated.

Thanks in advance for your help!

[steve2006]

Are there no fault codes present or stored? A diagnostic plug in should reveal the problem.

[ISRydr]

The error code that found is P1128 which I understand means Throttle Control Motor Lock Malfunction. Of late I'm hearing a whirring noise from the cone shaped attachment to the right of the throttle body. I hope it doesn't mean I've got to replace the whole throttle body but if I do any ideas where to buy a used one?

[1990LS400]

From the symptoms, it sounds like a failing TPS (throttle position sensor). Here is a thread about it: http://us.lexusownersclub.com/forums/topic/69501-unresponsive-gas-pedal-2000-ls-400/page__hl__throttle#entry434119

[landar]

So you take it to the Lexus dealer and an independent and they are both stumped? Then you turn to this forum and get lots of good suggestions. Speaks volumes about 'professional' help. Really sad these days! :cries: :D

[1990LS400]

So you take it to the Lexus dealer and an independent and they are both stumped? Then you turn to this forum and get lots of good suggestions. Speaks volumes about 'professional' help. Really sad these days! :cries: :D

Sad indeed. This is such a common problem on the 98-00 LS400 that anybody who regularly repairs them has to know what causes it. If they don't, they are either dishonest or clueless - take your pick.