Tap the gas... Stalls

[ryan_george]

Just trying to work out some minor issues with the new m20b25. When I depress the gas quickly, but only a tiny amount, the rpms drop down and it sometimes stalls. It does this whether it's cold or fully warmed up. I thought it might be the 02 sensor, but I just replaced that today and there's no change.
I haven't had the time yet to install the Check Engine Light, so I'm not even sure if that's trying to tell me something.
I'm running used wires, but the plugs, cap and rotor are new. I'm using m50 injectors with stock software (for now).

-Ryan

[Jordan]

Check your AFM

[nah325i]

I agree, sounds a lot like an AFM issue, that is unless the engine revs and then stalls as the rpms are returning to idle, that could be an icv issue.

[ryan_george]

Well I've finally had a chance to check the afm, and I think it's got issues. As I open the vane from closed to fully open, the resistance starts to increase, drops a little, increases a bit more, drops some more, then drops way off.
I took off the cover to have a look at the electronics, and everything is very clean and orderly. The resistive strip looks very good, with no scratches, knicks, dents, etc that would suggest it to be faulty.

Anybody have a 325i AFM for sale??