I've verified proper condition/function of all involved vacuum lines, the vacuum canister mounted on the accelerator pedal, as well as the cut-off on the brake pedal, both seem to function normally. The vacuum pump located under the battery tray pulls consistent vacuum when 12 volts is applied to the connector pins. I'm thinking the problem is electric/electronic in nature. Any hints on sensors/sending units/wiring I should check. The Chilton manual is next to useless on the subject, and I can't seem to find a schematic anywhere. Trying to avoid the dealers $85/hr charges...