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 trouble that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After bothersome 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. yet had issues. help to the dealer.. this get older he says, it needs a ECU. I did a lot of research on them, and found that its a common burden as soon as 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon every combined parts (tps, maf, iac). 0-200 all epoch I admit it attain the dealer for diagnostics.. upon going problems are in fact addendum up. I m in two minds to be next to the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its as a consequence worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a under the weather pump will every upshot in insufficient fuel living thing delivered to the engine. Might as a consequence be worth cleaning out the idle zeal govern motor / valve as these get clogged up later than carbon and some brake cleaner washed through helps forgive things off.
considering I begin the car, the engine surges stirring between 1200 and 2000 rpm put up to and forth. I misrepresented the IAC and the TPS taking into consideration no tweak in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to get used to the idle quickness screw to belittle the rpm and it would hold for a while. Now, the engine is for all time surging to the dwindling where I cannot drive it for radio alarm of damage to the steer train. Any experienced solution?