Engine racing

You just asked this question and got replies in alt.autos.pontiac. We still need the same info.

"John A. Hage" wrote: 2003 Pontiac Vibe.

Occasionally, when I brake, the engine starts racing - so much I have to push hard on the brake to keep it from zooming forward. Usually (not always) if I shift to neutral then back to drive, the engine quits racing. Then I have to turn it off and wait a while, then things are OK. The dealer couldn't find anything. Is there anything in particular I should ask the dealer to check?? ______________________________________________

2.) Braking action can also affect engine controls by upsetting vacuum flow. The dealer might look for:

a.) Loose or leaking vacuum line to carb/FI is starved by restore vacuum demand from brake booster.

b.) Disclosed crack in brake booster diaphragm drags down vacuum until brakes are released or until RPM is high enough to balance vacuum demand.

Good luck.

Wendy & John. ________________________________________________