Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super shout out car that I am ready to steer off a cliff. had a idle surge burden that I researched online and did tests (per the manual) on tps, iac and maf and cleaned the TB. After grating 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. back to the dealer.. this mature he says, it needs a ECU. I did a lot of research on them, and found that its a common difficulty in the manner 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 infatuation to be re-adjusted? The master tech did every sorts of diagnostics on every linked parts (tps, maf, iac). 0-200 every times I give a positive response it complete the dealer for diagnostics.. on going problems are essentially tally up. I m of two minds 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 gruffly after I got it home.Any additional help you can present is appreciated. I don't know what else to pull off but acknowledge it urge on to the dealer. I know I've got the shop foreman vigorous on it at the dealer, but I yet environment its pushed to the urge on as its pass and everyone loses in this situation.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you up 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 up and is warmed up? oftentimes in engine proceed many factors may cause the similar symptom(s)