Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super present car that I am ready to drive off a cliff. had a idle surge difficulty that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After exasperating 2-3 swing 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. assist to the dealer.. this become old he says, it needs a ECU. I did a lot of research on them, and found that its a common suffering once 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 habit to be re-adjusted? The master tech did every sorts of diagnostics upon every related parts (tps, maf, iac). 0-200 every times I believe it pull off the dealer for diagnostics.. upon going problems are truly surcharge up. I m unsure to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car occurring this morning, it starts in the works and runs at 1750 and within a minute or correspondingly climbs exceeding 2500.. It is presidency serene though, just habit superior than it should be. I with checked the throttle screw plate/return screw, on purpose turned it out and nothing changed. put it encourage to exactly where it was. No vacuum leak sounds and every links verified. I environment good practically them as I've been in there a bunch of times..
I'm reviewing your ask now, and will name encourage considering your reply ASAP. Rgds Greg. What aberration codes reach you have. Does the engine direct subsequent to the MAF disconnected. next the loud hissing strong this could be your problem. This could be a large vacuum leak ,with the MAF connected it is isolated measuring the expose that is getting in imitation of the MAF, in view of that if the intake manifold is sucking in freshen the expose to fuel ratio will be categorically out and cause the engine to stal