get rid the the BOV, that valve releases the pressure intake air to the atmosphere, the VAM measure the amount of air going into the intake form the fender/radiator area, when the BOV releases it lets out the air and the engien gets confuse
just block of the BOV and see what happens.
you need to run BPV (bypass valve) work the same but instead of lettign the out into the atmosphere it returns in from the inlet of the turbo. so no more metered air confusing.
Brian J Larkin
1988 Tbird TC 5spd. few bolt ons, 308k miles
1989 Cougar XR7 AOD 110k