Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast 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 exasperating 2-3 oscillate 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 grow old he says, it needs a ECU. I did a lot of research on them, and found that its a common problem behind 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 craving to be re-adjusted? The master tech did all sorts of diagnostics on every united parts (tps, maf, iac). 0-200 every mature I assume it complete the dealer for diagnostics.. on going problems are in point of fact calculation up. I m hesitant to be next to the tps if he had it dialed. Any insight? Thanks in advance. Jason
Might plus be worth checking the wiring and connector to the airflow meter for any signs of corrosion or damage. you can get a fast deformity find if you unplug the meter and manage the engine without it. if the engine condition is the same then chances are the meter or the relationship to it is faulty. Its afterward worth cleaning the MAF sensor wires, as they can get coated with dirt beyond time which next offsets the reading. Use some get into cleaner or brake cleaner to spray can onto the wires to cut off the dirt on no account touch the wires in the same way as all as they are definitely fragile
gone I begin the car, the engine surges happening together with 1200 and 2000 rpm urge on and forth. I changed the IAC and the TPS in the manner of no alter in symptoms. I have noticed that several Lexus SC's have this similar issue. Prior to this I would have to familiarize the idle zeal screw to belittle the rpm and it would hold for a while. Now, the engine is continuously surging to the point where I cannot steer it for terrify of damage to the steer train. Any experienced solution?