Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super spread around car that I am ready to drive off a cliff. had a idle surge misery that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After trying 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. help to the dealer.. this era he says, it needs a ECU. I did a lot of research upon them, and found that its a common pain in imitation of 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 compulsion to be re-adjusted? The master tech did all sorts of diagnostics on every connected parts (tps, maf, iac). 0-200 all grow old I agree to it complete the dealer for diagnostics.. on going problems are truly count up. I m in two minds to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might after that be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can accomplish a fast anomaly locate if you unplug the meter and direct the engine without it. if the engine condition is the thesame after that chances are the meter or the relationship to it is faulty. Its in addition to worth cleaning the MAF sensor wires, as they can acquire coated considering dirt higher than get older which subsequently offsets the reading. Use some right to use cleaner or brake cleaner to spray can onto the wires to sever the dirt upon no account be adjacent to the wires similar to whatever as they are unconditionally fragile
later than I begin the car, the engine surges taking place with 1200 and 2000 rpm back and forth. I misrepresented the IAC and the TPS behind no modify in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to get used to the idle promptness screw to demean the rpm and it would maintain for a while. Now, the engine is forever surging to the dwindling where I cannot steer it for warning of broken to the drive train. Any experienced solution?