Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to steer off a cliff. had a idle surge hardship that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After trying 2-3 every second 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. yet had issues. put up to to the dealer.. this get older he says, it needs a ECU. I did a lot of research upon them, and found that its a common hardship in the same way as this car.. bought a used one.. more trouble. had the native 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 on all connected parts (tps, maf, iac). 0-200 every become old I resign yourself to it realize the dealer for diagnostics.. on going problems are in point of fact tallying up. I m hesitant to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
I did re-check them tho. The master tech did extensive tests upon the expose flow meter and said it was good. similar to I unplug it and run the motor, the car runs unfriendly and at 850ish. I can single-handedly guess that my new rebuilt ecu has an issue, or the tps needs to be re-adjusted, or anyhow my maf has died in the midst of all this. I don't think the tps has that much govern in the every other of rpm though? I think it unaided adjusts it regarding 1k..
gone I start the car, the engine surges up surrounded by 1200 and 2000 rpm incite and forth. I changed the IAC and the TPS similar to no change in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to acclimatize the idle quickness screw to demean the rpm and it would keep for a while. Now, the engine is constantly surging to the tapering off where I cannot drive it for alarm bell of broken to the steer train. Any experienced solution?