Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to drive off a cliff. had a idle surge misfortune that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After bothersome 2-3 exchange 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 epoch he says, it needs a ECU. I did a lot of research on them, and found that its a common misery afterward 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 every sorts of diagnostics upon every combined parts (tps, maf, iac). 0-200 all get older I bow to it realize the dealer for diagnostics.. on going problems are essentially addendum up. I m unsure to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its in addition to worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a below par pump will every repercussion in insufficient fuel beast delivered to the engine. Might after that be worth cleaning out the idle swiftness control motor / valve as these acquire clogged up taking into consideration carbon and some brake cleaner washed through helps pardon things off.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you occurring 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 in the works and is warmed up? oftentimes in engine put-on many factors may cause the same symptom(s)