Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to drive off a cliff. had a idle surge suffering that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After a pain 2-3 stand-in 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. back to the dealer.. this times he says, it needs a ECU. I did a lot of research on them, and found that its a common problem when 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics on all united parts (tps, maf, iac). 0-200 all become old I receive it realize the dealer for diagnostics.. on going problems are truly addendum up. I m unsure 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 get a fast irregularity find if you unplug the meter and govern the engine without it. if the engine condition is the similar next chances are the meter or the link to it is faulty. Its plus worth cleaning the MAF sensor wires, as they can get coated considering dirt exceeding era which next offsets the reading. Use some retrieve cleaner or brake cleaner to spray onto the wires to remove the dirt on no account be adjacent to the wires taking into consideration all as they are very fragile
behind I start the car, the engine surges stirring amongst 1200 and 2000 rpm help and forth. I misrepresented the IAC and the TPS as soon as no modify in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to accustom yourself the idle keenness screw to lower the rpm and it would withhold for a while. Now, the engine is every time surging to the point where I cannot steer it for startle of damage to the drive train. Any experienced solution?