99gs400 Check Engine Light

[TRIPS]

Hello all, great to be a member here. I have a problem,and I hope someone may be able to help. two weeks ago I came out of a restaurant, and went to start the car it turned over once and then nothing. no lights no click etc. I called AAA,and they came and jumped it. it started but died when I put it in gear. the AAA driver said the battery was dead and needed replaced. this semmed possible since it is the original battery. fortunately there was an auto zone right across the street. I went over,and purchased a new battery and small crescent wrench. I installed new battery and started right up. everything seemed ok. two days later my wife calls me,and said the engine lost power,the check engine light,and VSC,VSC OFF lights were on. I went to pick her up, and as she said the lights were on,and when you mashed the throttle nothing.it would idle fine,but no throttle. I called AAA,to have it towed to our Lexus dealer,as we were waitng for the tow we had the car running to use the air conditioning suddenly the check engine,and VSC lights went off and throttle was back. The tow showed up and to the dealer it went,and I explained this whole senario. an hour later he calls,and says the performed all diagnostics and was normal. no codes were stored. He said maybe bad gas. any way today two weeks later my wife calls and says car is doing same thing. check engine,VSC,VSC OFF lights on no throttle. I went up and it was the same. I tried to give it throttle but you had to almost floor it for the engine to rev. sorry about the long post but I wanted to be clear so if this has happenened to someone else,they may be able to help. Thanks in advance.

[JimB]

There are two throttle position sensors that seem to have issues. Once upon a time, my symptoms were the same as yours. Lexus replaced on of the sensors and things seemed well. A few weeks later, the symptoms returned. Lexus replaced the second sensor to fix the issue. Be careful driving the car with this problem. It can be scary when the sensor fails while driving in traffic. Lexus should be able to easily diagnose this issue. Good luck.

[TRIPS]

There are two throttle position sensors that seem to have issues. Once upon a time, my symptoms were the same as yours. Lexus replaced on of the sensors and things seemed well. A few weeks later, the symptoms returned. Lexus replaced the second sensor to fix the issue. Be careful driving the car with this problem. It can be scary when the sensor fails while driving in traffic. Lexus should be able to easily diagnose this issue. Good luck.

Thanks for the reply, I just got it back from the dealer. they replaced the throttle position sensor,charged 127.00 for the part and 345.00 labor. the tech assured me this was the sensor that failed. he said there is another sensor ,but it checked out ok. he said because the car was in just two weeks ago and had no codes they did extensive diagnostics to ensure they corrected the problem this time. I sure hope he was right.