Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super spread around 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) upon tps, iac and maf and cleaned the TB. After aggravating 2-3 every second 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. put up to to the dealer.. this period he says, it needs a ECU. I did a lot of research upon them, and found that its a common hardship next this car.. bought a used one.. more trouble. had the original 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 craving to be re-adjusted? The master tech did all sorts of diagnostics on every connected parts (tps, maf, iac). 0-200 all epoch I tolerate it get the dealer for diagnostics.. on going problems are essentially extra up. I m hesitant to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its afterward worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a under the weather pump will every result in insufficient fuel physical delivered to the engine. Might as well as be worth cleaning out the idle quickness direct motor / valve as these acquire clogged in the works when 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 going on to date upon every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms up and is warmed up? oftentimes in engine performance many factors may cause the same symptom(s)