This could be an airleak after the airflow meter, any let breathe dragged in here isn t seen by the ECU and appropriately not compensated for and can lean the engine out and can in addition to allow the engine to rev up afterward not desired causing gruff running. As its a mechanical aberration it tends not to approach on the deviation vivacious and you can sometimes listen a hissing noise like 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 about the burden history. It currently has a master tech ascribed idle ventilate rule valve and tps installed. without disturbing anything, the last (used) ecu and my original, would govern in the car without this symptom.
as soon as I begin the car, the engine surges up amongst 1200 and 2000 rpm assist and forth. I misused the IAC and the TPS subsequently no regulate in symptoms. I have noticed that several Lexus SC's have this thesame issue. Prior to this I would have to adjust the idle swiftness screw to humiliate the rpm and it would maintain for a while. Now, the engine is every time surging to the point where I cannot drive it for clock radio of damage to the steer train. Any experienced solution?