brake booster runs off vac, get that vac leak fixed and you should be good.

Originalfrågan som referens skrev:

It doesn't do it all the time, but when I'm coming to a light and press on the brakes (normal rate), it dives under 700rpm and also looses charge in the battery from the usual 14V to around 12.5V.

My first instinct is these are signs of a dying alternator. And it could be, I have yet to replace it (134k miles). The battery hasn't been replaced in the 2.5 years I've had it, but it still holds a charge.

Could it be due to a vacuum leak? I do have an air leak in a hose on the top of the heads, coming off the main intake. Just called VW yesterday and it's $52. Gotta order it or just wrap some electrical tape around the hole.

Any suggestions?