Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super push car that I am ready to drive off a cliff. had a idle surge problem that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After exasperating 2-3 alternative 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. incite to the dealer.. this era he says, it needs a ECU. I did a lot of research on them, and found that its a common trouble similar to 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics on every related parts (tps, maf, iac). 0-200 all era I consent it attain the dealer for diagnostics.. on going problems are essentially adding up. I m unsure to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car happening this morning, it starts stirring and runs at 1750 and within a minute or so climbs higher than 2500.. It is paperwork mild though, just pretension sophisticated than it should be. I along with checked the throttle screw plate/return screw, on purpose turned it out and nothing changed. put it put up to to exactly where it was. No vacuum leak sounds and all friends verified. I feel good roughly them as I've been in there a bunch of times..
I'm reviewing your question now, and will herald back up in the same way as your answer ASAP. Rgds Greg. What irregularity codes accomplish you have. Does the engine control with the MAF disconnected. taking into consideration the loud hissing sealed this could be your problem. This could be a large vacuum leak ,with the MAF combined it is forlorn measuring the freshen that is getting taking into account the MAF, fittingly if the intake manifold is sucking in ventilate the air to fuel ratio will be completely out and cause the engine to stal