Hi, this car is kicking everyone s ass.. 92 lexus sc400. 128k. Super broadcast car that I am ready to steer off a cliff. had a idle surge problem that I researched online and did tests (per the manual) upon tps, iac and maf and cleaned the TB. After a pain 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. assist to the dealer.. this period he says, it needs a ECU. I did a lot of research upon them, and found that its a common burden subsequent to this car.. bought a used one.. more trouble. had the native 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 linked parts (tps, maf, iac). 0-200 all period I assume it complete the dealer for diagnostics.. on going problems are in point of fact totaling up. I m hesitant to lie alongside the tps if he had it dialed. Any insight? Thanks in advance. Jason
I'm 1500 too high.. or more. It's boggling to me how this problem has morphed into various idle problems and has everyone perplexed.. or for that reason it seems. I've been dealing gone this back July.. makes me appreciate my 240z 10 time more.My father owns an sc400 and its been in reality fine to him.. I'm having a difficult times not creature mordant next this purchase. I reach character taking into consideration its a good car though. Motor sounds lovely and is super smooth once dispensation right.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you happening 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 play in many factors may cause the thesame symptom(s)