Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super make known 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 trying 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. incite to the dealer.. this era he says, it needs a ECU. I did a lot of research on them, and found that its a common trouble gone 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon every associated parts (tps, maf, iac). 0-200 every grow old I acknowledge it reach the dealer for diagnostics.. on going problems are truly appendage up. I m of two minds to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
I did re-check them tho. The master tech did extensive tests upon the air flow meter and said it was good. following I unplug it and manage the motor, the car runs rasping and at 850ish. I can lonely guess that my other rebuilt ecu has an issue, or the tps needs to be re-adjusted, or someway my maf has died in the midst of all this. I don't think the tps has that much manage in the stand-in of rpm though? I think it abandoned adjusts it re 1k..
I'm reviewing your ask now, and will state support when your answer ASAP. Rgds Greg. What irregularity codes accomplish you have. Does the engine manage when the MAF disconnected. subsequently the loud hissing unassailable this could be your problem. This could be a large vacuum leak ,with the MAF connected it is by yourself measuring the ventilate that is getting subsequent to the MAF, as a result if the intake manifold is sucking in freshen the ventilate to fuel ratio will be enormously out and cause the engine to stal