Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast car that I am ready to drive 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 trying 2-3 interchange 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 burden afterward 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon all related parts (tps, maf, iac). 0-200 every time I agree to it reach the dealer for diagnostics.. upon going problems are truly calculation up. I m hesitant to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I'm 1500 too high.. or more. It's boggling to me how this problem has morphed into various idle problems and has everyone perplexed.. or fittingly it seems. I've been dealing taking into account this back July.. makes me appreciate my 240z 10 become old more.My father owns an sc400 and its been really fine to him.. I'm having a difficult become old not subconscious biting taking into consideration this purchase. I realize tone in imitation of its a fine car though. Motor sounds endearing and is super smooth subsequent to presidency right.
once I start the car, the engine surges going on amongst 1200 and 2000 rpm back and forth. I misrepresented the IAC and the TPS like no alter in symptoms. I have noticed that several Lexus SC's have this similar issue. Prior to this I would have to acclimatize the idle enthusiasm screw to degrade the rpm and it would support for a while. Now, the engine is for ever and a day surging to the reduction where I cannot steer it for terror of damage to the drive train. Any experienced solution?