Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super market 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) on tps, iac and maf and cleaned the TB. After irritating 2-3 different 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. assist to the dealer.. this get older he says, it needs a ECU. I did a lot of research upon them, and found that its a common misfortune like 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 all amalgamated parts (tps, maf, iac). 0-200 every time I take it get the dealer for diagnostics.. on going problems are truly totaling up. I m hesitant to touch the tps if he had it dialed. Any insight? Thanks in advance. Jason
I bought it in July, drove it house from LA (to Utah), and the problems started immediately after I got it home.Any other encourage you can manage to pay for is appreciated. I don't know what else to realize but understand it assist to the dealer. I know I've got the shop foreman vigorous on it at the dealer, but I yet atmosphere its pushed to the back as its old-fashioned and everyone loses in this situation.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you taking place to date on all maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms stirring and is warmed up? oftentimes in engine play a part many factors may cause the same symptom(s)