Well, after finally curing all my previous idle problems (TPS and gummed up accelerator cable) a new one has crept up...

I'm pretty confident that it's a vacuum leak in the brake booster somewhere, but was curious if anyone had any insight as to common places, or just to tell me I'm waaayyy off.

Anywho, basically, the car idles fine, cold, warm, whatever, until I get on the brakes, then the idle drops to 350 or so and bounces till I get off of them. It VERY occasionally does it at a stop as well, but that's a VERY VERY rare occurance. It runs strong throughout the powerband, just an issue with the braking.. so, yes, any ideas, before I start attacking vacuum lines?

 

There is a diaphragm in the booster assembly. If it tears you get your problems.