Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super announce car that I am ready to steer off a cliff. had a idle surge hardship that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After bothersome 2-3 different 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. assist 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 burden afterward 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 dependence to be re-adjusted? The master tech did every sorts of diagnostics upon every aligned parts (tps, maf, iac). 0-200 every epoch I consent it realize the dealer for diagnostics.. on going problems are essentially accumulation up. I m unsure 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 not quite the suffering history. It currently has a master tech endorsed idle air govern valve and tps installed. without touching anything, the last (used) ecu and my original, would direct in the car without this symptom.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you in the works 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 in the works and is warmed up? oftentimes in engine exploit many factors may cause the same symptom(s)