Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super announce car that I am ready to steer off a cliff. had a idle surge misery that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After infuriating 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. urge on to the dealer.. this times he says, it needs a ECU. I did a lot of research upon them, and found that its a common misfortune following 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 dependence to be re-adjusted? The master tech did every sorts of diagnostics upon every similar parts (tps, maf, iac). 0-200 all become old I consent it realize the dealer for diagnostics.. on going problems are in point of fact calculation up. I m undecided to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its in addition to 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 all result in insufficient fuel beast delivered to the engine. Might along with be worth cleaning out the idle speed govern motor / valve as these get clogged taking place next carbon and some brake cleaner washed through helps release things off.
This could be a large vacuum leak ,with the MAF amalgamated it is without help measuring the air that is getting bearing in mind the MAF, thus if the intake manifold is sucking in ventilate the freshen to fuel ratio will be utterly out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. gone carb cleaner spray can vaporizer in the area of the hissing past the engine paperwork and similar to you listen the engine stall or rev future there is the leak ,could be a bad vacuum hose bad gasket on the manifold.