Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast 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 exasperating 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. nevertheless had issues. help to the dealer.. this grow old he says, it needs a ECU. I did a lot of research upon them, and found that its a common pain gone 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 all sorts of diagnostics upon all connected parts (tps, maf, iac). 0-200 every mature I assume it attain the dealer for diagnostics.. on going problems are in point of fact adding up. I m hesitant to adjoin 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 upon the ventilate flow meter and said it was good. taking into consideration I unplug it and govern the motor, the car runs scratchy and at 850ish. I can unaccompanied guess that my further rebuilt ecu has an issue, or the tps needs to be re-adjusted, or somehow my maf has died in the midst of all this. I don't think the tps has that much direct in the different of rpm though? I think it without help adjusts it nearly 1k..
This could be a large vacuum leak ,with the MAF similar it is forlorn measuring the expose that is getting in the same way as the MAF, consequently if the intake manifold is sucking in ventilate the let breathe to fuel ratio will be unquestionably out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. subsequently carb cleaner spray spray in the area of the hissing subsequent to the engine organization and past you listen the engine stall or rev forward-looking there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.