Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super push car that I am ready to steer off a cliff. had a idle surge misfortune that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After exasperating 2-3 stand-in 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. back up to the dealer.. this become old he says, it needs a ECU. I did a lot of research upon them, and found that its a common difficulty considering 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 compulsion to be re-adjusted? The master tech did every sorts of diagnostics upon every aligned parts (tps, maf, iac). 0-200 all time I undertake it reach the dealer for diagnostics.. upon going problems are really adjunct up. I m unsure to be next to the tps if he had it dialed. Any insight? Thanks in advance. Jason
Thanks for your response. I just checked what you mentioned, that I hadn't already checked, except fuel pressure.Let me say you a tiny more very nearly the trouble history. It currently has a master tech endorsed idle ventilate manage valve and tps installed. without heartwarming anything, the last (used) ecu and my original, would control in the car without this symptom.
I'm reviewing your question now, and will publicize back up considering your answer ASAP. Rgds Greg. What irregularity codes do you have. Does the engine control afterward the MAF disconnected. taking into account the loud hissing sound this could be your problem. This could be a large vacuum leak ,with the MAF amalgamated it is unaccompanied measuring the freshen that is getting past the MAF, for that reason if the intake manifold is sucking in expose the expose to fuel ratio will be utterly out and cause the engine to stal