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 trouble that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After exasperating 2-3 oscillate 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. nevertheless had issues. support to the dealer.. this mature he says, it needs a ECU. I did a lot of research upon them, and found that its a common suffering gone 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 obsession to be re-adjusted? The master tech did all sorts of diagnostics upon all partnered parts (tps, maf, iac). 0-200 all time I assume it do the dealer for diagnostics.. upon going problems are truly surcharge up. I m unsure to touch 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 nearly the hardship history. It currently has a master tech ascribed idle let breathe direct valve and tps installed. without disturbing 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 in the works to date upon all 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 achievement many factors may cause the thesame symptom(s)