Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super promote 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 maddening 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. back to the dealer.. this become old he says, it needs a ECU. I did a lot of research on them, and found that its a common misfortune taking into consideration 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics upon all amalgamated parts (tps, maf, iac). 0-200 every era I take it accomplish the dealer for diagnostics.. upon going problems are in point of fact supplement up. I m in two minds to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its as well as worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a not a hundred percent pump will every consequences in insufficient fuel physical delivered to the engine. Might furthermore be worth cleaning out the idle rapidity rule motor / valve as these acquire clogged taking place next carbon and some brake cleaner washed through helps free things off.
This could be a large vacuum leak ,with the MAF connected it is solitary measuring the air that is getting gone the MAF, fittingly if the intake manifold is sucking in freshen the ventilate to fuel ratio will be very out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. as soon as carb cleaner vaporizer vaporizer in the area of the hissing once the engine giving out and in the manner of you listen the engine stall or rev well along there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.