Shaggs2Dope
New Member
I have searched the numerous idle issues on the forum, and none of them seem to make a difference. I have checked the entire intake, and it is a tight system, no leaks, no vacuum issues. I was driving my girlfriends 90 LS400 and it just started accelerating on me with my foot not on the gas. If I let it go it gets up to about 50mph by itself in gear. In Idle it revs at 1500rpms or so at startup, and then switches to 2krpm jump-down to 1k, back to 2k every half second or so. It really pulls and surges at stoplights like it wants to launch into the car in front of me. I am just glad I upgraded her rotors and pads to cross drilled slotted with metal masters, or it would have rear ended someone.
The only thing I can think is that the car sat for a long time, and has some old fuel and marvel mystery oil in it. Plus, I washed the car off, including the engine bay a lil bit but kept it away from intake, mainly rinsed the belts since they are screechin a bit, even with belt dressing, which usually means they have someantifreze on the belts.
Anyway, there is no check engine light, the car has ran fine until this point at 245k miles. I know on hondas it is usually Idle Air Control valve or vacuum leak, and most imports its a gross leak after Mass Air Flow sensor. Do the Air flow sensors go out a lot on the lexus LS, because I have seen a TON of threads on here about them being faulty. I had the MAF go out on a mitsu I had and it would hunt because it is stuck in a loop.
Anyone else find a remedy for this. I really hope its not MAF because they are usually expensive. And I dont have the lexus code reader, even though there is no engine light, I can't plug in the diagnostic port.
The only thing I can think is that the car sat for a long time, and has some old fuel and marvel mystery oil in it. Plus, I washed the car off, including the engine bay a lil bit but kept it away from intake, mainly rinsed the belts since they are screechin a bit, even with belt dressing, which usually means they have someantifreze on the belts.
Anyway, there is no check engine light, the car has ran fine until this point at 245k miles. I know on hondas it is usually Idle Air Control valve or vacuum leak, and most imports its a gross leak after Mass Air Flow sensor. Do the Air flow sensors go out a lot on the lexus LS, because I have seen a TON of threads on here about them being faulty. I had the MAF go out on a mitsu I had and it would hunt because it is stuck in a loop.
Anyone else find a remedy for this. I really hope its not MAF because they are usually expensive. And I dont have the lexus code reader, even though there is no engine light, I can't plug in the diagnostic port.