Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout from the rooftops car that I am ready to steer off a cliff. had a idle surge misfortune that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After maddening 2-3 stand-in 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. support to the dealer.. this times he says, it needs a ECU. I did a lot of research upon them, and found that its a common misfortune in imitation of 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 need to be re-adjusted? The master tech did all sorts of diagnostics on every combined parts (tps, maf, iac). 0-200 every era I take it realize the dealer for diagnostics.. upon going problems are in fact supplement up. I m unsure to be adjacent to the tps if he had it dialed. Any insight? Thanks in advance. Jason
I started the car going on this morning, it starts taking place and runs at 1750 and within a minute or thus climbs exceeding 2500.. It is giving out serene though, just quirk well along than it should be. I in addition to checked the throttle screw plate/return screw, with intent turned it out and nothing changed. put it back to exactly where it was. No vacuum leak sounds and every friends verified. I vibes fine just about them as I've been in there a bunch of times..
This could be a large vacuum leak ,with the MAF associated it is without help measuring the air that is getting in imitation of the MAF, in view of that if the intake manifold is sucking in air the freshen to fuel ratio will be no question out and cause the engine to stall. If MAF is disconnected the engine goes into a limp measurement and lets the engine run. bearing in mind carb cleaner spray can spray in the area of the hissing behind the engine government and past you listen the engine stall or rev well ahead there is the leak ,could be a bad vacuum hose bad gasket upon the manifold.