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) upon tps, iac and maf and cleaned the TB. After trying 2-3 every other 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. put up to to the dealer.. this epoch he says, it needs a ECU. I did a lot of research upon them, and found that its a common hardship similar to 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 dependence to be re-adjusted? The master tech did every sorts of diagnostics on all partnered parts (tps, maf, iac). 0-200 every grow old I assume it accomplish the dealer for diagnostics.. on going problems are in point of fact totaling up. I m unsure to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its along with worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a not at your best pump will every outcome in insufficient fuel brute delivered to the engine. Might then be worth cleaning out the idle speed govern motor / valve as these acquire clogged taking place taking into consideration carbon and some brake cleaner washed through helps free things off.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you taking place to date on all 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 operate many factors may cause the thesame symptom(s)