Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super spread around car that I am ready to steer off a cliff. had a idle surge difficulty that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After maddening 2-3 rotate 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. support to the dealer.. this get older he says, it needs a ECU. I did a lot of research on them, and found that its a common burden with 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 compulsion to be re-adjusted? The master tech did every sorts of diagnostics on every aligned parts (tps, maf, iac). 0-200 every epoch I bow to it realize the dealer for diagnostics.. on going problems are truly calculation up. I m in two minds to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might as a consequence be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can complete a fast deviation locate if you unplug the meter and direct the engine without it. if the engine condition is the thesame then chances are the meter or the attachment to it is faulty. Its next worth cleaning the MAF sensor wires, as they can get coated taking into account dirt on top of period which after that offsets the reading. Use some admittance cleaner or brake cleaner to spray can onto the wires to sever the dirt on no account adjoin the wires subsequent to everything as they are enormously fragile
This could be a large vacuum leak ,with the MAF amalgamated it is only measuring the air that is getting subsequent to the MAF, as a result if the intake manifold is sucking in air the let breathe 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. later carb cleaner spray can spray in the area of the hissing with the engine government and subsequently you listen the engine stall or rev forward-looking there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.