98 ls400 problem on startup
#1
Pole Position
Thread Starter
98 ls400 problem on startup
A about 2 or 3 times a month when I start the car the rpms jump up and down from 400-700. If I tap the gas pedal or put it in drive it stop and goes back to normal. It only does it on start up every once in awhile. This is on a 98 ls400. Anyone have a clue as to what it could be?
#6
Pole Position
It could also be the IACV starting to go bad or really dirty and needs to be cleaned. I'm not saying that is the problem but here's some reading material; http://www.planetsoarer.com/IAC/iac.htm
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#8
Clean the throttle body. Has no IACV and a vacuum leak would be constant. Relearn the idle afterwards. Does the car have a weak battery? If so, the voltage may be dropping low enough for the ECU to forget the idle position. Cleaning the TB will allow air past the plate even if this occurs.
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