Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super publicize 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) on tps, iac and maf and cleaned the TB. After trying 2-3 swap 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 time he says, it needs a ECU. I did a lot of research on them, and found that its a common problem in the same way as this car.. bought a used one.. more trouble. had the original 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 all sorts of diagnostics upon all associated parts (tps, maf, iac). 0-200 all times I tolerate it complete the dealer for diagnostics.. on going problems are really tallying up. I m of two minds to adjoin 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 pull off a quick aberration find if you unplug the meter and govern the engine without it. if the engine condition is the similar after that chances are the meter or the membership to it is faulty. Its then worth cleaning the MAF sensor wires, as they can acquire coated once dirt beyond period which next offsets the reading. Use some gain access to cleaner or brake cleaner to spray can onto the wires to cut off the dirt upon no account be adjacent to the wires afterward whatever as they are unquestionably fragile
This could be a large vacuum leak ,with the MAF related it is only measuring the expose that is getting similar to the MAF, correspondingly if the intake manifold is sucking in expose the expose to fuel ratio will be totally out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. behind carb cleaner spray spray can in the place of the hissing later the engine supervision and similar to you listen the engine stall or rev higher there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.