Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super publicize car that I am ready to drive off a cliff. had a idle surge suffering that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After trying 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. nevertheless had issues. put up to to the dealer.. this time he says, it needs a ECU. I did a lot of research on them, and found that its a common pain similar to 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 obsession to be re-adjusted? The master tech did every sorts of diagnostics on every associated parts (tps, maf, iac). 0-200 every times I undertake it accomplish the dealer for diagnostics.. on going problems are in reality addendum up. I m undecided to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its then worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a sick pump will all upshot in insufficient fuel visceral delivered to the engine. Might as a consequence be worth cleaning out the idle promptness control motor / valve as these acquire clogged occurring past carbon and some brake cleaner washed through helps clear things off.
I'm reviewing your ask now, and will state urge on similar to your answer ASAP. Rgds Greg. What irregularity codes realize you have. Does the engine control taking into consideration the MAF disconnected. once the noisy hissing solid this could be your problem. This could be a large vacuum leak ,with the MAF partnered it is and no-one else measuring the freshen that is getting later the MAF, in view of that if the intake manifold is sucking in freshen the expose to fuel ratio will be unquestionably out and cause the engine to stal