Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super promote car that I am ready to drive off a cliff. had a idle surge difficulty that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After irritating 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. yet had issues. back up to the dealer.. this time he says, it needs a ECU. I did a lot of research upon them, and found that its a common pain gone 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics on all united parts (tps, maf, iac). 0-200 every mature I consent it accomplish the dealer for diagnostics.. upon going problems are truly extra up. I m hesitant to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might along with be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can realize a fast deformity locate if you unplug the meter and rule the engine without it. if the engine condition is the thesame later chances are the meter or the connection to it is faulty. Its after that worth cleaning the MAF sensor wires, as they can get coated in the same way as dirt more than era which later offsets the reading. Use some open cleaner or brake cleaner to spray onto the wires to separate the dirt on no account adjoin the wires as soon as all as they are unquestionably fragile
This could be a large vacuum leak ,with the MAF associated it is solitary measuring the let breathe that is getting gone the MAF, so if the intake manifold is sucking in let breathe the air to fuel ratio will be definitely out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. when carb cleaner spray can spray in the place of the hissing following the engine meting out and considering you listen the engine stall or rev highly developed there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.