This could be an airleak after the airflow meter, any ventilate dragged in here isn t seen by the ECU and therefore not compensated for and can lean the engine out and can then allow the engine to rev going on later than not desired causing scratchy running. As its a mechanical fault it tends not to viewpoint on the deformity light and you can sometimes hear a hissing noise taking into account the engine running.
I started the car up this morning, it starts stirring and runs at 1750 and within a minute or for that reason climbs more than 2500.. It is processing mild though, just quirk well along than it should be. I in addition to checked the throttle screw plate/return screw, carefully turned it out and nothing changed. put it put up to to exactly where it was. No vacuum leak sounds and every connections verified. I air good nearly them as I've been in there a bunch of times..
I don't have any check engine lights unless I unplug the MAF sensor. in the same way as the MAF is plugged in after that the car will stall unless I put my foot upon the accelerator. There is next an intermittent popping sealed coming at idle.