Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super promote car that I am ready to steer off a cliff. had a idle surge misery that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After maddening 2-3 substitute 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. encourage 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 burden 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 craving to be re-adjusted? The master tech did every sorts of diagnostics upon every combined parts (tps, maf, iac). 0-200 every time I recognize it attain the dealer for diagnostics.. upon going problems are in reality adjunct up. I m hesitant to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might then be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can do a quick irregularity locate if you unplug the meter and rule the engine without it. if the engine condition is the similar next chances are the meter or the connection to it is faulty. Its plus worth cleaning the MAF sensor wires, as they can acquire coated like dirt on top of get older which next offsets the reading. Use some contact cleaner or brake cleaner to spray onto the wires to separate the dirt on no account be adjacent to the wires taking into account anything as they are enormously fragile
subsequent to I start the car, the engine surges occurring with 1200 and 2000 rpm urge on and forth. I distorted the IAC and the TPS following no amend in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to adjust the idle swiftness screw to demean the rpm and it would retain for a while. Now, the engine is continually surging to the tapering off where I cannot drive it for startle of damage to the drive train. Any experienced solution?