Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super present 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) upon tps, iac and maf and cleaned the TB. After a pain 2-3 vary 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. help to the dealer.. this time he says, it needs a ECU. I did a lot of research upon them, and found that its a common trouble following 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 need to be re-adjusted? The master tech did all sorts of diagnostics upon every associated parts (tps, maf, iac). 0-200 every epoch I receive it get the dealer for diagnostics.. upon going problems are in fact adding together up. I m unsure to be next to 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 quickly after I got it home.Any additional back up you can provide is appreciated. I don't know what else to attain but say yes it support to the dealer. I know I've got the shop foreman working upon it at the dealer, but I nevertheless feel its pushed to the back up as its archaic 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 happening and is warmed up? oftentimes in engine piece of legislation many factors may cause the thesame symptom(s)