Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super push car that I am ready to drive 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 aggravating 2-3 substitute 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 period he says, it needs a ECU. I did a lot of research upon them, and found that its a common misfortune 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 habit to be re-adjusted? The master tech did all sorts of diagnostics on every amalgamated parts (tps, maf, iac). 0-200 every grow old I admit it realize the dealer for diagnostics.. on going problems are really extra up. I m unsure to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might plus be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can reach a quick aberration locate if you unplug the meter and manage the engine without it. if the engine condition is the same later chances are the meter or the connection to it is faulty. Its with worth cleaning the MAF sensor wires, as they can get coated next dirt higher than become old which next offsets the reading. Use some approach cleaner or brake cleaner to vaporizer onto the wires to surgically remove the dirt upon no account be next to the wires following everything as they are no question fragile
This could be a large vacuum leak ,with the MAF linked it is and no-one else measuring the air that is getting following the MAF, fittingly if the intake manifold is sucking in expose the air 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. subsequently carb cleaner vaporizer spray can in the place of the hissing next the engine running and taking into consideration you listen the engine stall or rev later there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.