Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to steer 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 frustrating 2-3 swing 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. urge on 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 trouble once 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 obsession to be re-adjusted? The master tech did all sorts of diagnostics on all associated parts (tps, maf, iac). 0-200 all period I agree to it reach the dealer for diagnostics.. on going problems are really adding up up. I m of two minds to be adjacent to 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 expose flow meter and said it was good. later than I unplug it and direct the motor, the car runs brusque and at 850ish. I can forlorn guess that my additional rebuilt ecu has an issue, or the tps needs to be re-adjusted, or anyhow my maf has died in the midst of all this. I don't think the tps has that much govern in the alternative of rpm though? I think it isolated adjusts it with reference to 1k..
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you occurring 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 occurring and is warmed up? oftentimes in engine act out many factors may cause the similar symptom(s)