Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super present 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 irritating 2-3 swing 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. put up to to the dealer.. this mature he says, it needs a ECU. I did a lot of research on them, and found that its a common misfortune afterward 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon every related parts (tps, maf, iac). 0-200 all times I consent it realize the dealer for diagnostics.. on going problems are in point of fact toting up up. I m in two minds to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might moreover be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can realize a fast aberration locate if you unplug the meter and run the engine without it. if the engine condition is the similar subsequently chances are the meter or the link to it is faulty. Its as a consequence worth cleaning the MAF sensor wires, as they can get coated later than dirt on top of epoch which next offsets the reading. Use some retrieve cleaner or brake cleaner to vaporizer onto the wires to separate the dirt on no account lie alongside the wires past anything as they are categorically fragile
This could be a large vacuum leak ,with the MAF linked it is and no-one else measuring the ventilate that is getting later the MAF, as a result if the intake manifold is sucking in let breathe the air to fuel ratio will be enormously out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. afterward carb cleaner vaporizer spray in the area of the hissing bearing in mind the engine organization and next you hear the engine stall or rev well along there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.