Hi folks,

My 88 740T has an acceleration problem thats been going on for a while. If the car has been sitting for a few minutes with the engine off, it will accelerate hard in first gear until the boost gauge begins climbing past about 2/3 max boost, then the acceleration stops abruptly. Once it has done this once, it will accelerate poorly throughout the entire rpm and boost range. If you shut the car off for a little while it does the same thing again. The engine does not cut out, no smoke, no back-fire, no knocking... just no power.

I have replaced the mass air sensor, the foam in the air filter box has been removed, the plugs are new (the old ones showed normal light gray deposits), and it has a new distributer. I'm beginning to think that an intake air hose is collapsing under acceleration, but I have no idea which one to start with.

Any ideas?

 

Does it do it stationary or just under load?