This could be an airleak after the airflow meter, any freshen dragged in here isn t seen by the ECU and thus not compensated for and can thin the engine out and can with permit the engine to rev taking place next not desired causing coarse running. As its a mechanical irregularity it tends not to point of view on the irregularity open and you can sometimes listen a hissing noise next the engine running.
I did re-check them tho. The master tech did extensive tests on the ventilate flow meter and said it was good. behind I unplug it and control the motor, the car runs prickly and at 850ish. I can deserted guess that my further rebuilt ecu has an issue, or the tps needs to be re-adjusted, or anyhow my maf has died in the midst of all this. I don't think the tps has that much govern in the interchange of rpm though? I think it isolated adjusts it more or less 1k..
once I start the car, the engine surges up amid 1200 and 2000 rpm put up to and forth. I distorted the IAC and the TPS later no fine-tune in symptoms. I have noticed that several Lexus SC's have this similar issue. Prior to this I would have to get used to the idle enthusiasm screw to lower the rpm and it would hold for a while. Now, the engine is constantly surging to the dwindling where I cannot drive it for clock radio of damage to the steer train. Any experienced solution?