I have a 95 Bonnie, non super charged. This is my issue. Intermittent rpm bounce. Usually while driving freeway speeds the motor will almost stall out. The odometer needle bounces all over the place. The car almost stalls out. Feels like a trans issue however it doesnt stop once the vehicle is in park, or neutral. The check engine light comes on and everything smooths out. The codes are "loss of boost" and vacuum leak. The motor and trans were rebuilt about a year ago. I have checked the plugs and wires. I have also replaced the throttle position sensor after reading a TSB from alldata.com. Has anyone dealt with this or heard of it? Please help me. A couple of times while on the freeway it almost felt like the motor was gonna drop out of the car. It has been pretty violent at times. By the way it is a series 2, the VIN code is "K".

Thanks for any help or ideas.
Ryan

You have a vacuum leak. Locate it and fix it.

A simple vacuum leak can cause havoc! Get a can of Carb and Choke cleaner, with the engine running, spray it all around your throttle body area, ALL of the plastic vacuum tubing that has those rubber couplings. They are prone to dry rot and will crack causing leaks. If you find cracked couplings, and can't find the replacements at any store, pickup a tube of black RTV silicone sealant. With the engine off, dab some on the cracks sealing them up.

Do you know if the crank sensor was replaced at the time of the engine build?

I'm not aware of a code for "vacuum leak", please post the code number so we can check Techinfo for other possiblie help as well.