DannyBlake10

hey guys i think my power booster has gone bad. i have good vacuum going to it, and the check valve is good. if i dont use the brakes for a while they work great, but if im on and off them a lot i lose power brakes and am stuck with manual brakes until i let off for a little

like i said, i think its the booster. i think there is a leak in the diaphram in it. Do you guys have any input or different ideas as to what it might be?

also, where are some good places to get a new vacuum booster?

JackDidley

Its the booster. Autozone had one last year for $120 out the door.

coupeguy2001

I bought the Auto Zone one about 3 years ago, and it works just fine.

DannyBlake10

pefect
thanks

Black89Z51

Start the car and put your head near the pedals. Apply the brake with your hand. If the diaphragm is bad in the booster you may hear a slight hissing coming from the firewall area where the pedal rod goes through.

If you have to change out the booster, I wish you the best. The fasteners on the inside are the worst to get to. Take the seat out and lay in the floorboard upside down. That is probably the best position to get to them.

oldalaskaman

theres a metal one that interchanges with the stock plastic one, its a bit cheaper and works just a good

DannyBlake10

Yes I do hear hissing when the Pedal is pressed
And that's what I'm afraid of, I had a feeling its a lot of work. Probably about the same as when we mounted the hydraboost brakes on my dads c3

Black89Z51

It's really not that much work. It just a pure pain in the *** to get the thing bolted in place. You don't even have to take the brake lines off the MC. And the seat is only 4 nuts.

A little hint, pack bearing grease into a socket to hold the nuts in there while you fish your extension and universal up there.

pcolt94

Just installed a booster 6 months ago and got it from AutoZone. The booster worked great with no problem and the brakes are better now than they have been since 04 when I got the car.

The old booster had no symptoms of being bad those years till it went bad and leaked. It just did not work that well but appeared to be normal. Good thing is the AutoZone booster is lifetime guaranteed.

70ZZ3 96LT4

Like others have posted I have replaced the vacuum brake booster on my 1985. I also bought the replacement from Auto Zone. This was several years ago, however the replacement was an exact replacement made by the same manufacturer of the 85's original factory installed booster. It was around $100 when I bought mine years ago, but was a lot less than the same product if purchased from the GM parts counter.

DannyBlake10

so i started taking the seat out. got the four bolts undone and got to the electical. there are two wiring bundles. there was a plug on one, which i unhooked, but i cant find out where the second one disconnects. it is the one completely wrapped in electrical tape. any body know where this plug is?

a454corvette

On mine (92 with sport seats), it was up inside the black shroud under the seat, and very difficult to fish out of the access hole. I wound up moving the seat assembly forward of the mount studs and tipping it back to access the connector.

FWIW, don't bolt the booster to the firewall before you get the pushrod on the pedal pin....guess how I know

DannyBlake10

got it done today. didnt end up taking the seat out. just unbolted it so i could get a little more clearance

the biggest problem i ran into was moving that rail that goes from the frame under the cruise control module up to the firewall where the hood latch it. but once it was out, the job wasnt too bad. once i found a 'comfortable' position upside down under the pedals, it was pretty ok