Evening all;

This vehicle has a severe flat spot under acceleration and if accelerator is blipped quickly will stall on return to idle. No flat-spot is evident when conducting this test in neutral. The engine management system includes a moving flap AFM with adjustable mixture air bleed screw, a single wire o2 sensor and MAP sensor. I believe the MAP sensor is there for the Turbo. I have adjusted the mixture by turning the mixture bleed screw until the o2 sensor can "cope" with it and start switching in the normal fashion in an acceptable manner. CO is approx 1.4%, HC is 120ppm, CO2 is about12.6% and o2 a little high at about 2.6% (twin big bore exhausts). At fast idle, the CO is a bit high at about 3.6%. I believe there is an AFM issue but for some reason will not pico-scope. On a digital multi-meter we have 2.5v at idle and dropping to about 1v at fast idle. I would expect to see the opposite but rising to 4.5v at fast idle. On inspection the moving flap is free in movement but appears to be mis-aligned. Are these findings just peculiar to the TCCS system or do I fork out for another AFM?
Would value your thoughts.

Regards

Pete M