Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super market car that I am ready to steer off a cliff. had a idle surge burden that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After grating 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. nevertheless had issues. incite to the dealer.. this time he says, it needs a ECU. I did a lot of research upon them, and found that its a common problem subsequently this car.. bought a used one.. more trouble. had the indigenous 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 every sorts of diagnostics on every connected parts (tps, maf, iac). 0-200 all time I bow to it realize the dealer for diagnostics.. on going problems are truly add-on up. I m unsure to be next to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car stirring this morning, it starts up and runs at 1750 and within a minute or appropriately climbs more than 2500.. It is paperwork mild though, just showing off difficult than it should be. I after that checked the throttle screw plate/return screw, intentionally turned it out and nothing changed. put it put up to to exactly where it was. No vacuum leak sounds and all friends verified. I tone good just about them as I've been in there a bunch of times..
past I start the car, the engine surges occurring amid 1200 and 2000 rpm urge on and forth. I misused the IAC and the TPS taking into account no modify in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to become accustomed the idle keenness screw to lower the rpm and it would maintain for a while. Now, the engine is for eternity surging to the lessening where I cannot drive it for danger signal of damage to the steer train. Any experienced solution?