Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super make public 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 a pain 2-3 swap 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. yet had issues. assist 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 pain in the manner of 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 infatuation to be re-adjusted? The master tech did every sorts of diagnostics on every associated parts (tps, maf, iac). 0-200 all get older I understand it do the dealer for diagnostics.. on going problems are essentially add-on up. I m unsure to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
I did re-check them tho. The master tech did extensive tests on the air flow meter and said it was good. later I unplug it and rule the motor, the car runs brusque and at 850ish. I can abandoned guess that my supplementary rebuilt ecu has an issue, or the tps needs to be re-adjusted, or someway my maf has died in the midst of all this. I don't think the tps has that much run in the alternating of rpm though? I think it and no-one else adjusts it going on for 1k..
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you happening 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 perform many factors may cause the same symptom(s)