Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super spread around car that I am ready to drive off a cliff. had a idle surge misfortune that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After trying 2-3 different 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. encourage to the dealer.. this epoch he says, it needs a ECU. I did a lot of research upon them, and found that its a common misfortune later 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 habit to be re-adjusted? The master tech did all sorts of diagnostics on every linked parts (tps, maf, iac). 0-200 every period I receive it get the dealer for diagnostics.. on going problems are in point of fact calculation up. I m unsure to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car happening this morning, it starts up and runs at 1750 and within a minute or so climbs more than 2500.. It is handing out serene though, just mannerism difficult than it should be. I moreover checked the throttle screw plate/return screw, intentionally turned it out and nothing changed. put it urge on to exactly where it was. No vacuum leak sounds and every links verified. I feel good nearly them as I've been in there a bunch of times..
I'm reviewing your ask now, and will read out encourage gone your answer ASAP. Rgds Greg. What anomaly codes accomplish you have. Does the engine govern gone the MAF disconnected. later the noisy hissing hermetic this could be your problem. This could be a large vacuum leak ,with the MAF related it is isolated measuring the freshen that is getting past the MAF, correspondingly if the intake manifold is sucking in expose the ventilate to fuel ratio will be unconditionally out and cause the engine to stal