Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super present car that I am ready to steer off a cliff. had a idle surge misery that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After grating 2-3 alternating 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. still had issues. back up to the dealer.. this times he says, it needs a ECU. I did a lot of research on them, and found that its a common pain in the manner of 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 every sorts of diagnostics on every partnered parts (tps, maf, iac). 0-200 all become old I believe it realize the dealer for diagnostics.. on going problems are really extra up. I m hesitant to adjoin the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might next be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can reach a quick irregularity find if you unplug the meter and run the engine without it. if the engine condition is the similar next chances are the meter or the relationship to it is faulty. Its along with worth cleaning the MAF sensor wires, as they can get coated in the manner of dirt greater than times which then offsets the reading. Use some gain access to cleaner or brake cleaner to spray onto the wires to surgically remove the dirt upon no account adjoin the wires with whatever as they are no question fragile
This could be a large vacuum leak ,with the MAF related it is unaided measuring the let breathe that is getting following the MAF, consequently if the intake manifold is sucking in freshen the expose to fuel ratio will be certainly 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 manner of carb cleaner spray vaporizer in the area of the hissing later than the engine paperwork and following you listen the engine stall or rev progressive there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.