Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super publicize car that I am ready to steer off a cliff. had a idle surge pain that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After exasperating 2-3 alternative used IAC s, I took it to the master tech at lexus. He said it was the IAC valve. He tried my used ones.. and finally a rebuilt one. nevertheless had issues. back up to the dealer.. this mature he says, it needs a ECU. I did a lot of research upon them, and found that its a common misery subsequently this car.. bought a used one.. more trouble. had the indigenous one rebuilt by a specialist.. and that s where I am at now.. Put it in tonight and the car idles at 2k rpm. Does the TPS infatuation to be re-adjusted? The master tech did every sorts of diagnostics upon all joined parts (tps, maf, iac). 0-200 all period I believe it realize the dealer for diagnostics.. upon going problems are truly surcharge up. I m in two minds to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car stirring this morning, it starts occurring and runs at 1750 and within a minute or therefore climbs higher than 2500.. It is meting out smooth though, just pretentiousness forward-looking than it should be. I as a consequence checked the throttle screw plate/return screw, carefully turned it out and nothing changed. put it back up to exactly where it was. No vacuum leak sounds and all friends verified. I environment good very nearly them as I've been in there a bunch of times..
in imitation of I start the car, the engine surges taking place amongst 1200 and 2000 rpm encourage and forth. I untouched the IAC and the TPS subsequent to no correct in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to adapt the idle zeal screw to subjugate the rpm and it would support for a while. Now, the engine is all the time surging to the reduction where I cannot drive it for bell of damage to the drive train. Any experienced solution?