sweeper

I have a 2000 Xj with ABS breaks. When I first start it and take off for the day the power breaks won't work untill I reach 25mph, then they will work fine. Unless I drive a short distance, 5 miles or so, it does it all over when I start it back up. To me it acts like a bad booster with a slight leak. I replaced the booster and it still does it. I have noticed a clicking in the center console area around the shifter that stops when I reach the 25mph range. I'm lost on what to do next. Please help I jumped a curb last night and about hit a building. That would have been embarissing.

No one knows?

Its lonely in here.

echooo echoooo echoooooo LOL

walwal63

A simple thing that I would check is the check valve on the vacuum line. That is what holds a vacuum in the booster when the engine is shut off. If it is bleeding out when you have it parked it could take a moment to refill that booster. You can check it simply, you should be able to blow through it but not suck through it.

Bustedback

Push the brake pedal before you start the engine. If it is rock hard it means you have a vacuum leak. The check valve on the booster could be the problem.

sweeper

Thanks guys I will check that out.Booster came with a new check valve, but that doesn't mean it is good it is a reman from NAPA.

Whent out and tried the pedal and it's not rock hard,Harder than when its running but not super hard. I checked the check valve and it seems to be good. I sprayed WD40 around the vacume lines earlyer (was told this would rev the engine if I had a leak) and nothing happened. Could something in the ABS box with all the lines coming out of it be causing this ? Or what about wheel sensors?

Mmurdock

Did you bleed all your brake lines when you swapped out the brake booster? Even if you did you may still have some air in the lines causing the brakes to be spongy until they've been pumped up a little. Try bleeding the system again starting with the brake furthest from the reservoir and work your way to the closest. When the brake fluid is clear and free of air bubbles you are done with that brake.

The problem could also be caused by a damaged brake hose or line, or a leaky wheel cylinder or caliper. Pull the wheels one at a time and inspect the brakes, then crawl underneath and inspect the lines.

I would not recommend driving this vehicle until the problem is solved, it's not just your life at risk. If you can't figure it out on your own have it towed to a professional, it will be less expensive than your insurance deductable.

sweeper

I didn't have to break the lines to change the booster, and I have crawled all under it and don't have any break fluid leaks (I think everything else is leaking tho) So I guess a trip to the garage is about my next choice.

Mmurdock

Try bleeding the brakes. If you've never done it before find a friend who has (it takes two people anyway unless you have a vacuum bleeding tool). All you need is a wrench to crack open the bleed screws, a couple feet clear tubing which fits snuggly over the nipple on the bleed screw, a plastic bottle, and a large bottle of fresh brake fluid. Should cost less than $10 and take less than an hour.

There should also be several videos on how to do this on YouTube.

walwal63

So is the pedal hard to push when it is happening or does the pedal go down with no braking?

sweeper

OK first I want to think everyone for helping. Now I'm sorry for wasting your tme, after trying and doing everything youall said I checked the ABS light and the bulb is bad. so the whole time its been in the abs system. sorry forfor any confusion. I still need help tho.I have a 2000 Xj with ABS breaks. When I first start it and take off for the day the power breaks won't work untill I reach 25mph, then they will work fine. Unless I drive a short distance, 5 miles or so, it does it all over when I start it back up. To me it acts like a bad booster with a slight leak. The ABS light is on after I travel a 100 yrards or so.