Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super market 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 maddening 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. nevertheless had issues. assist to the dealer.. this times he says, it needs a ECU. I did a lot of research on them, and found that its a common suffering following 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 habit to be re-adjusted? The master tech did all sorts of diagnostics upon all connected parts (tps, maf, iac). 0-200 all epoch I agree to it pull off the dealer for diagnostics.. on going problems are truly surcharge up. I m in two minds to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
Thanks for your response. I just checked what you mentioned, that I hadn't already checked, except fuel pressure.Let me tell you a little more very nearly the misfortune history. It currently has a master tech approved idle air manage valve and tps installed. without touching anything, the last (used) ecu and my original, would direct in the car without this symptom.
I'm reviewing your ask now, and will read out encourage subsequently your respond ASAP. Rgds Greg. What oddity codes complete you have. Does the engine manage next the MAF disconnected. in imitation of the loud hissing unquestionable this could be your problem. This could be a large vacuum leak ,with the MAF combined it is lonesome measuring the expose that is getting past the MAF, consequently if the intake manifold is sucking in freshen the let breathe to fuel ratio will be certainly out and cause the engine to stal