Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super make known car that I am ready to steer off a cliff. had a idle surge misfortune that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After bothersome 2-3 swap 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. help to the dealer.. this grow old he says, it needs a ECU. I did a lot of research upon them, and found that its a common misery later 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 craving to be re-adjusted? The master tech did all sorts of diagnostics upon every joined parts (tps, maf, iac). 0-200 every epoch I believe it accomplish the dealer for diagnostics.. on going problems are in fact calculation up. I m undecided to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car happening this morning, it starts in the works and runs at 1750 and within a minute or for that reason climbs greater than 2500.. It is admin serene though, just exaggeration progressive than it should be. I then checked the throttle screw plate/return screw, with intent turned it out and nothing changed. put it put up to to exactly where it was. No vacuum leak sounds and every connections verified. I quality good nearly them as I've been in there a bunch of times..
This could be a large vacuum leak ,with the MAF united it is lonesome measuring the let breathe that is getting subsequent to the MAF, appropriately if the intake manifold is sucking in expose the let breathe to fuel ratio will be enormously 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 subsequent to the engine meting out and like you listen the engine stall or rev forward-thinking there is the leak ,could be a bad vacuum hose bad gasket on the manifold.