Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to steer off a cliff. had a idle surge trouble that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After irritating 2-3 substitute 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. help to the dealer.. this become old he says, it needs a ECU. I did a lot of research on them, and found that its a common difficulty next this car.. bought a used one.. more trouble. had the native 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 compulsion to be re-adjusted? The master tech did every sorts of diagnostics upon every amalgamated parts (tps, maf, iac). 0-200 every get older I agree to it complete the dealer for diagnostics.. upon going problems are essentially tallying 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 happening and runs at 1750 and within a minute or suitably climbs greater than 2500.. It is handing out mild though, just pretentiousness well ahead than it should be. I with checked the throttle screw plate/return screw, purposefully turned it out and nothing changed. put it back to exactly where it was. No vacuum leak sounds and every contacts verified. I quality fine more or less them as I've been in there a bunch of times..
taking into account I start the car, the engine surges occurring amongst 1200 and 2000 rpm back and forth. I misused the IAC and the TPS later than no fiddle with in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to acclimatize the idle quickness screw to degrade the rpm and it would keep for a while. Now, the engine is forever surging to the dwindling where I cannot drive it for bell of broken to the steer train. Any experienced solution?