Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super puff 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 maddening 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. still had issues. back to the dealer.. this grow old he says, it needs a ECU. I did a lot of research upon them, and found that its a common difficulty following 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 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 admit it pull off the dealer for diagnostics.. on going problems are in point of fact addendum up. I m of two minds to lie alongside 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 tell you a tiny more not quite the trouble history. It currently has a master tech official idle let breathe control valve and tps installed. without upsetting anything, the last (used) ecu and my original, would run in the car without this symptom.
I don't have any check engine lights unless I unplug the MAF sensor. in the same way as the MAF is plugged in subsequently the car will stall unless I put my foot upon the accelerator. There is in addition to an intermittent popping sound coming at idle.