This could be an airleak after the airflow meter, any freshen 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 as a consequence permit the engine to rev taking place later not desired causing coarse running. As its a mechanical defect it tends not to aim on the deformity buoyant and you can sometimes listen a hissing noise with the engine running.
Thanks for your response. I just checked what you mentioned, that I hadn't already checked, except fuel pressure.Let me tell you a tiny more practically the hardship history. It currently has a master tech attributed idle freshen manage valve and tps installed. without moving anything, the last (used) ecu and my original, would govern in the car without this symptom.
considering I begin the car, the engine surges in the works amid 1200 and 2000 rpm back and forth. I misrepresented the IAC and the TPS gone no alter in symptoms. I have noticed that several Lexus SC's have this same issue. Prior to this I would have to adapt the idle rapidity screw to lower the rpm and it would support for a while. Now, the engine is for ever and a day surging to the reduction where I cannot drive it for warning of broken to the drive train. Any experienced solution?