Dave,

I think Steve is right, I bet the trim is incorrectly adjusted or the pot is slightly off alignment. I am amazed that you were able to remove it and install it in the exact same position as the old one given its location and the amount of injection pieces surrounding it. (For those not familiar with the 16V motor, they are a complete bear to work on)

I check the pot number on mine (87 16V) and it is the same number that Steve posted 3437.224.035. I ran the number you posted through a Bosch parts source and nothing came up.

Try to readjust as Steve stated and post your results.

Tinker