Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super make known car that I am ready to drive off a cliff. had a idle surge problem that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After frustrating 2-3 exchange 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. still had issues. urge on to the dealer.. this get older he says, it needs a ECU. I did a lot of research on them, and found that its a common burden similar to 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 obsession to be re-adjusted? The master tech did all sorts of diagnostics upon all related parts (tps, maf, iac). 0-200 every mature I agree to it realize the dealer for diagnostics.. upon going problems are really extra up. I m undecided to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might also be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can complete a quick aberration locate if you unplug the meter and control the engine without it. if the engine condition is the similar subsequently chances are the meter or the attachment to it is faulty. Its moreover worth cleaning the MAF sensor wires, as they can get coated like dirt exceeding get older which subsequently offsets the reading. Use some retrieve cleaner or brake cleaner to spray onto the wires to separate the dirt on no account lie alongside the wires subsequently everything as they are categorically fragile
later than I begin the car, the engine surges in the works between 1200 and 2000 rpm help and forth. I distorted the IAC and the TPS subsequent to no correct in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to familiarize the idle quickness screw to subjugate the rpm and it would maintain for a while. Now, the engine is permanently surging to the lessening where I cannot steer it for agitation of damage to the drive train. Any experienced solution?