I would say the motor is hitting a form of fuel cut. you will need a missing link or an electronic FCD. Not all cars react to positive pressure the same way. some fall flat on thier face others like mine just hiccup.

A type of voltage clamp should clear up your problem. why you are seeing it now and not so much before could be because the motor is different.

A megasquirt will solve the problem since the ECU uses the injectors to create the situation. Grain on this site uses the MS with no voltage clamp and he does not have the slightest problem.



Terry