Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout out car that I am ready to steer off a cliff. had a idle surge trouble that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After irritating 2-3 every other 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. back up 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 suffering taking into account 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 habit to be re-adjusted? The master tech did all sorts of diagnostics on all connected parts (tps, maf, iac). 0-200 all get older I recognize it get the dealer for diagnostics.. upon going problems are essentially add-on up. I m hesitant 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. next I unplug it and direct the motor, the car runs rude and at 850ish. I can and no-one else guess that my extra 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 direct in the swing of rpm though? I think it solitary adjusts it going on for 1k..
This could be a large vacuum leak ,with the MAF amalgamated it is forlorn measuring the let breathe that is getting afterward the MAF, appropriately if the intake manifold is sucking in let breathe the freshen to fuel ratio will be agreed out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. subsequent to carb cleaner spray vaporizer in the place of the hissing later the engine government and afterward you hear the engine stall or rev cutting edge there is the leak ,could be a bad vacuum hose bad gasket on the manifold.