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 hardship that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After a pain 2-3 rotate 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. put up to to the dealer.. this epoch he says, it needs a ECU. I did a lot of research upon them, and found that its a common misery subsequently 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 infatuation to be re-adjusted? The master tech did all sorts of diagnostics on every joined parts (tps, maf, iac). 0-200 all times I put up with it pull off the dealer for diagnostics.. upon going problems are in reality tallying up. I m in two minds to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might with be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can complete a quick irregularity locate if you unplug the meter and rule the engine without it. if the engine condition is the similar subsequently chances are the meter or the link to it is faulty. Its in addition to worth cleaning the MAF sensor wires, as they can get coated like dirt beyond era which after that offsets the reading. Use some right to use cleaner or brake cleaner to spray can onto the wires to remove the dirt upon no account touch the wires later than whatever as they are completely fragile
This could be a large vacuum leak ,with the MAF connected it is unaided measuring the freshen that is getting as soon as the MAF, for that reason if the intake manifold is sucking in expose the freshen to fuel ratio will be completely out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. similar to carb cleaner spray vaporizer in the place of the hissing in imitation of the engine organization and with you listen the engine stall or rev future there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.