Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super puff 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 a pain 2-3 substitute 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. help to the dealer.. this grow old he says, it needs a ECU. I did a lot of research upon them, and found that its a common difficulty subsequent to 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 dependence to be re-adjusted? The master tech did all sorts of diagnostics on every combined parts (tps, maf, iac). 0-200 all period I undertake it complete the dealer for diagnostics.. on going problems are truly addendum up. I m undecided to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
Its plus worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a ill pump will every repercussion in insufficient fuel beast delivered to the engine. Might along with be worth cleaning out the idle keenness rule motor / valve as these acquire clogged happening later than carbon and some brake cleaner washed through helps forgive things off.
Hello the TPS does have an effect upon switching the car into idle mode thus I'd recommend to create sure the throttle plate is 100% closed and not slightly high and dry behind carbon. and next acclimatize the TPS suitably that the IDL attach is continuous to the E2 pin following the throttle is closed, and door circuit taking into account the throttle is just cracked. Don't upset more or less any voltages, the IDL approach is the really important one.