A finicky power brake boosterl

Dear Car Talk

Dear Car Talk | May 01, 1993

Dear Tom and Ray:

I have an ?"89 Chevrolet Caprice Classic with 35,000 miles. I have driven cars for a long time, but have never had this happen before. For the last two months, every time I put on the brakes, a loud sound of escaping air comes up from the floor from down around the brake pedal. Other than that, the brakes seem to work normally. I took it to the dealer, and then to another person who runs a repair shop. They both drove the car and listened, but didn?ot know what the problem was. I want to get the car repaired, but would like to take it where they have experience with this kind of problem. Can you help?

RAY: Well, Daniel, unless your Caprice is the "Peterbilt Edition..." the one with air brakes, mud flaps, and the name "Betsy" written across the grille, then I'd say you have a bad power brake booster.

TOM: The power brake booster is a vacuum operated device that provides the "power" in power brakes. Your system has a hole in it, and what you're hearing is air being sucked into that hole. The hole might be in the booster's diaphragm, or in the hose that leads to the booster.

RAY: You say the brakes seem normal, but I'll bet they're not. And they may get worse all of a sudden, So you really do need to get this fixed. If it fails completely, it's going to take all the strength you've got to stop this two ton Caprice.

TOM: And where should you take it? Well, I certainly wouldn't take it back to either of the two ding-a-lings who didn't know what it was.

RAY: On second thought, you could take it back to that Chevy dealer. Wait til the booster gets worse, and then drive right up to the showroom window. At the last second, hit the brakes. When the dealer comes running in to see who went through the plate glass window and smashed into the ZR-1 Corvette on display, give him a shrug and ask him if he wants to take another look at the brakes for you.

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