This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and in view of that not compensated for and can thin the engine out and can in addition to permit the engine to rev happening in the manner of not desired causing harsh running. As its a mechanical aberration it tends not to incline on the malformation light and you can sometimes listen a hissing noise like the engine running.
I'm 1500 too high.. or more. It's boggling to me how this trouble has morphed into various idle problems and has everyone perplexed.. or correspondingly it seems. I've been dealing in the manner of this past July.. makes me appreciate my 240z 10 times more.My father owns an sc400 and its been in reality good to him.. I'm having a hard era not innate sour later than this purchase. I get feel with its a fine car though. Motor sounds delectable and is super serene with organization right.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you in the works to date on every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms in the works and is warmed up? oftentimes in engine conduct yourself many factors may cause the similar symptom(s)