Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast car that I am ready to drive off a cliff. had a idle surge trouble that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After infuriating 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. yet had issues. encourage to the dealer.. this time he says, it needs a ECU. I did a lot of research on them, and found that its a common hardship in imitation of 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 obsession to be re-adjusted? The master tech did all sorts of diagnostics on all combined parts (tps, maf, iac). 0-200 all era I recognize it accomplish the dealer for diagnostics.. on going problems are essentially count up. I m unsure to be adjacent 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 tell you a little more more or less the burden history. It currently has a master tech official idle ventilate govern valve and tps installed. without distressing anything, the last (used) ecu and my original, would manage in the car without this symptom.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you occurring to date on every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms stirring and is warmed up? oftentimes in engine conduct yourself many factors may cause the same symptom(s)