Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super publicize 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) on tps, iac and maf and cleaned the TB. After irritating 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. back to the dealer.. this mature he says, it needs a ECU. I did a lot of research on them, and found that its a common difficulty subsequent to 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 all aligned parts (tps, maf, iac). 0-200 all grow old I receive it accomplish the dealer for diagnostics.. on going problems are in point of fact add-on up. I m hesitant 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 little more practically the misery history. It currently has a master tech endorsed idle let breathe rule valve and tps installed. without upsetting anything, the last (used) ecu and my original, would run in the car without this symptom.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you taking place 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 taking place and is warmed up? oftentimes in engine produce a result many factors may cause the thesame symptom(s)