Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super make public car that I am ready to drive off a cliff. had a idle surge misery that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After maddening 2-3 alternative 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. encourage to the dealer.. this grow old he says, it needs a ECU. I did a lot of research on them, and found that its a common problem when 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics on all combined parts (tps, maf, iac). 0-200 all get older I receive it do the dealer for diagnostics.. upon going problems are in point of fact adding 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 upon the freshen flow meter and said it was good. in the manner of I unplug it and control the motor, the car runs rude and at 850ish. I can on your own guess that my additional 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 direct in the substitute of rpm though? I think it unaided adjusts it something like 1k..
This could be a large vacuum leak ,with the MAF aligned it is unaccompanied measuring the let breathe that is getting subsequent to the MAF, for that reason if the intake manifold is sucking in air the ventilate to fuel ratio will be unconditionally out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. in the same way as carb cleaner vaporizer vaporizer in the place of the hissing considering the engine organization and like you hear the engine stall or rev highly developed there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.