My 2 WD comanche has a brake noise when you depress the pedal. It sounds like air leaking until the pedal is fully depressed. I thought it was the brake booster, but when I use my repair book diagnostics, it doesn't seem so. We have replaced pads and the master cylinder in the last year and bled the brakes but the vacuum noise persists. Any help would be appreciated
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
You may have air in your braking system. You will need to bleed your brakes.
Some people say it is ok to just bleed the front brake that is on the same side as the master cylinder. I personally feel that all 4 brakes should be bled.
On each caliper/drum there should be a small nipple type fitting with a (usually) 8mm nut at its base. Loosening this nut will allow brake fluid to seep from the nipple opening.
Work with a partner. Remove your first wheel of the brake to be worked on. Loosen the 8mm nut. Have your assistant depress the brake pedal steadily to the floor and hold. If a steady stream of fluid comes out tighten the nut and move on to the next brake. If the brake fluid comes out sputtering with air, tighten the nut after your assistant depressed the brake (but ensure they kept the pedal to the floor). Have them take their foot off the brake. Loosen the nut again and have them depress the brake fully again. Repeat until steady stream of fluid comes out with no air.
Do this for all 4 brakes.
Once complete refill the reservoir to the recommended fill line.
Especially with noises, it's nearly impossible to diagnose without being there. The noise you are hearing may be the first indication of your catalytic converter beginning to fail. As the exhaust gets squeezed through a smaller and smaller opening it can make that kind of noise. If the engine is running rough at idle, I'd also check for vacuum leaks.
has your brake pedal seem to be stiffer than usual? the sound you hear is from the brake booster if it has a leak it will cause a noise but you would have a stiffer pedal because the booster is loosing vacuum.