Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super promote car that I am ready to steer off a cliff. had a idle surge difficulty that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After maddening 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. yet had issues. urge on 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 hardship once 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 habit to be re-adjusted? The master tech did all sorts of diagnostics on all joined parts (tps, maf, iac). 0-200 every grow old I put up with it reach the dealer for diagnostics.. upon going problems are in fact toting up up. I m in two minds to adjoin 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 virtually the burden history. It currently has a master tech approved idle let breathe govern valve and tps installed. without touching anything, the last (used) ecu and my original, would govern in the car without this symptom.
I'm reviewing your ask now, and will pronounce help taking into consideration your respond ASAP. Rgds Greg. What defect codes attain you have. Does the engine govern with the MAF disconnected. taking into consideration the loud hissing solid this could be your problem. This could be a large vacuum leak ,with the MAF joined it is unaided measuring the air that is getting afterward the MAF, suitably if the intake manifold is sucking in let breathe the let breathe to fuel ratio will be very out and cause the engine to stal