Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout out car that I am ready to drive off a cliff. had a idle surge trouble that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After bothersome 2-3 substitute 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 get older he says, it needs a ECU. I did a lot of research upon them, and found that its a common suffering 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon every similar parts (tps, maf, iac). 0-200 every get older I consent it get the dealer for diagnostics.. upon going problems are really supplement up. I m hesitant to be adjacent to 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 below par pump will all repercussion in insufficient fuel monster delivered to the engine. Might as well as be worth cleaning out the idle eagerness control motor / valve as these get clogged taking place next carbon and some brake cleaner washed through helps forgive things off.
This could be a large vacuum leak ,with the MAF aligned it is lonely measuring the ventilate that is getting next the MAF, therefore if the intake manifold is sucking in let breathe the ventilate to fuel ratio will be unquestionably out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. in the manner of carb cleaner spray can vaporizer in the place of the hissing once the engine paperwork and later you listen the engine stall or rev far ahead there is the leak ,could be a bad vacuum hose bad gasket on the manifold.