Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast car that I am ready to steer off a cliff. had a idle surge trouble that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After bothersome 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. nevertheless had issues. assist to the dealer.. this epoch he says, it needs a ECU. I did a lot of research on them, and found that its a common pain when 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 infatuation to be re-adjusted? The master tech did every sorts of diagnostics on all similar parts (tps, maf, iac). 0-200 all era I agree to it accomplish the dealer for diagnostics.. upon going problems are in reality appendage up. I m in two minds to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its along with worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a under the weather pump will every upshot in insufficient fuel swine delivered to the engine. Might as a consequence be worth cleaning out the idle speed manage motor / valve as these get clogged in the works bearing in mind carbon and some brake cleaner washed through helps release things off.
This could be a large vacuum leak ,with the MAF linked it is unaided measuring the freshen that is getting subsequent to the MAF, so if the intake manifold is sucking in freshen the air 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. next carb cleaner spray vaporizer in the place of the hissing behind the engine paperwork and like you listen the engine stall or rev well ahead there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.