Bill L Seifert

I just got the new top on our 1998 Boxster. It has the hard window and looks great.

But a wierd thing happened on the way home. When I step on the brakes the nose dips and for about 1/2 a second the car stops normally, but then the car does not seem to have much in the way of brake power. It is like the front brakes are not working. The pedal is hard, but the car just does not stop as it should. The car had sit for 2 days with the low 9 degrees, and a high of 22, so I thought maybe something was frozen. But it is over 30 miles to my house, and I tried the brakes dozens of times, which should have thawed anything frozen out. I couldn't see anything last night, but this morning I looked at the brake pads and they look ok, as to the discs. No warning lights are illuminated. As a matter of fact, the warning lights work as they should. When the ignition comes on the lights come on, then after starting the engine the lights go out as they should.

Any ideas?

Bill Seifert

1998 Boxster (95,000 miles)

986Jim

Brake fluid does not freeze so no worries there, it works the same in freezing temperatures as it does in hot temperatures. I would say you either have air in the lines which is slowing the reaction down and not giving enough pressure, or you have a leak in the system somewhere and the fluid is leaking out causing low pressure. Either way it seems like your master cylinder is not able to provide the pressure to the calipers that it should.

99firehawk

open tre front trunk
remove the battery cover and the drivers side cover
in the wll you should see a rubber bellow that covers the push rod for the master cylinder.
pull the bellow back is the linkage all rusty? if it is the well probaly flodded at one time or another due to clogged drains and the brake booster probaly has water in it

Bill L Seifert

Thanks, I'll check all that. However, I doubt the low on fluid or air in brake lines. I've had low fluid and air several time on my 944 Race Car, and the pedal always goes to the floor, not feel normal and hard. Of course, Boxsters could be different. Brad, by bellow, are you talking about the brake booster?

Thanks fellas

Bill

99firehawk

theres a rubber tube that fits over the linkage from the booster to the master, it was chnaged in 99-00 to a new style that prevents water from entering the booster.
if thats your problem youll need a booster and the update kit

NOTE TO ALL CHECK AND CLEAN THE DRAINS IN THE FRONT AND BACK OF YOUR CARS MONTHLY

Bill L Seifert

It does not look like there has been water in that compartment, except for the fact that the two bolts, that, I guess, hold the master cylinder on look a little rusty.

The boot that covers the linkage is acually two. One from the firewall back, and one from the wall of the trunk going forward. I tried to pry both back with a screwdriver, but I didn't want to poke a hole through them. Should I use a pry bar?

Thanks,

Bill

99firehawk

usually you can tell theres been water in there, the horn is rusty the battery tray is rusty, evry piec of exposed metal. Iy does sound like a brake booster issue, not enough vacum or a failed booster to me

Bill L Seifert

Brad, I'll have the booster checked out on Monday. There is no rust anywhere, except on the nuts that hold the master cylinder on. Everything else is like brand new. It is up to about 50 degrees now, and I just took the car out, and the brakes work as they should. I would guess that ice somewhere was causing the problem, because it was 10 or 12 degrees when I picked the car up, and had been below freezing for 2 days. It's going to be upper 50's for the next week, and I will keep it under the carport.

As soon as I get the old 944 race car the rest of the way stripped, I am going to have it hauled off, and put the Boxster in the garage for the rest of the winter, except I will probably take it to Daytona for Christmas.

Thanks a bunch,

Bill

deliriousga

Brake fluid does not freeze, but the water that it likes to grab out of the air does. If you don't know when the fluid was last changed, I'd change it all out including through the clutch slave. It should be done at least once every two years. Just get yourself a power bleeder if you don't have one and it's an easy one man job.

Bill L Seifert

deliriousga

Why the heck did I not think of that. I honestly can't remember the last time the brake fluid was changed. I know it has been at least 3 years I am ashamed to say.

By the way folks, I am going to post the installation of the new hard window top in another thread.

Thanks everyone,

Bill