paradox

I'm so glad that this problem was finally resolved. Been following this thread from the onset, and I can imagine how frustrating the experience was, especially being so protracted. Hopefully, you've re evaluated your decision to sell the Lex, and you can finally get to enjoy it.

timgs300

iTrader: (22)

Sorry I didn't read this earlier. Same exact thing happened to me when I had a 98 GS3. TPS was at fault for that.

hegar817

Ok, I just changed my spark plugs to NGK Iridium and also noticed the symptoms( vsc off, vsc , cel lights on but with a good throttle) also noticed that the GS300 would back fire when accelerating the engine under stress and cel would start blinking. Do you guys think its the plugs? Had no issue with it until the plugs were changed. By the way I already tried changing the throttle body with my friends GS with TPS and throttle sensor attached.

Any suggestions?

hegar817

How do you adjust the TPS?

loud3nergy

the two screws holding it in have some adusting room, with the engine started we would rotate it until the idle was normal.

gs30062-1

there is a calibration to set up the apps and tps if the ecu sees them off a little it disables throttle motor this has to be done with a scan tool prob had a bad tps or apps but never saw a change because you didnt set it up right. just dumb luck you got it to work.

erics3000

I have never adjusted a tps for any of my lexus's but on my other cars I always used a DVM. Like mentioned above you loosen the 2 screws that hold the TPS and adjust until you get the required voltage from the manufactures recommendations. Not sure if they are any other steps to the process for lexus but it has always been a simple straight procedure to adjust a tps. Any time you remove 1 you should readjust, or check if your model needs to be adjusted. But like I mentioned things are always changing. Not even sure how the drive by wire works now.

marus

iTrader: (1)

wow.... i think i had a similiar issue the ecu must be changed.....

Rob1799

YEA, I have a 2001 GS 430 130k miles and I have dealt with most of these problems...
I was using a oil cold air filter which was gumming up the MAF, replaced it a couple times before I realized it could be cleaned with Break Parts Cleaner. Got into an accident which when fixed somehow exposed the VSC sensors, so when it rains or when I drive through puddles the VSC lights show up, when it drys out they go away. I cooked my CATS, they both went between 120-130k miles... The initial ECU code was for the EVAP system. I never replaced that and the CATS came up 10k miles later. I have the check engine on again, I bet it's the EVAP. Water and oil on sensors seems to be a responsible for much of the problems I have had.