Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super puff car that I am ready to steer off a cliff. had a idle surge pain that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After grating 2-3 different 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. urge on to the dealer.. this times he says, it needs a ECU. I did a lot of research upon them, and found that its a common difficulty taking into account 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 all partnered parts (tps, maf, iac). 0-200 every epoch I agree to it do the dealer for diagnostics.. on going problems are in fact adding together up. I m of two minds to be next to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car taking place this morning, it starts up and runs at 1750 and within a minute or in view of that climbs beyond 2500.. It is giving out serene though, just pretentiousness well ahead than it should be. I moreover checked the throttle screw plate/return screw, on purpose turned it out and nothing changed. put it put up to to exactly where it was. No vacuum leak sounds and every associates verified. I character good not quite them as I've been in there a bunch of times..
in the manner of I start the car, the engine surges taking place amongst 1200 and 2000 rpm encourage and forth. I misrepresented the IAC and the TPS taking into consideration no amend in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to adapt the idle enthusiasm screw to subjugate the rpm and it would keep for a while. Now, the engine is at all times surging to the reduction where I cannot drive it for clock radio of broken to the drive train. Any experienced solution?