On my lincoln mkx 07 when i press the brake it sounds like air coming out and sometimes the pedal is hard

Paul W

• 404 Answers
• Posted on Jan 22, 2009

SOURCE: Hissing sound from brake pedal of Renault Scenic 2001

Hi,
From your description this appears to be a Brake servo issue.
The brakes are assisted by a vacuum created from the draw off the inlet manifold, it gives assistance too the brake pedal pressure by a large tank/cylinder mounted on the Bulkhead/firewall.
I feel that the sound you a hearing is air being draw into the Brake Servo from the foot pedal seal and the reason for fluctuation in the engine is the vacuum from the inlet manifold is being upset.
Attention I suspect should be addressed to the Brake servo/pedal seal or gaitor.
I hope this clarifies your thoughts?
Please remember to rate my effort.
Paul 'W'
Onyer~EDSon(:0) {#><U.K.

Ned C Cook

• 3433 Answers
• Posted on May 25, 2009

SOURCE: hard brake pedal hear air leaking when pedal pushed

When you press on the brake? Have your brake vacuum assist checked. It,s that bigspaceship looking thing between the brake master cylinder an firewall. good luck and be safe.

SOURCE: when i step on the brake pedal i hear air coming

This perfectly describes a failure of the brake vacuum booster.
Replace the power brake vacuum booster.

SOURCE: 2001 Chrysler Concorde pressed the brake

That sound you hear is coming from the Vauum Brake Booster...Sooner or later the Brake Pedal will get hard, because the seal inside of the Brake Booster is leaking..And the only way to repair it, is , to replace the Brake Booster...But also check your Vacuum Hose that is instaaled on your Brake Booster..It goes from the Brake Booster, which is behind the Master Cylinder...From there to the Intake Manifold...Just make sure that there are no cracks in that hose, and make sure it is on all the way...because if the hose is bad, then thats all you will have to replace....Goodluck...

SOURCE: clicking sound when i press the gas pedal

The clicking and popping sound like a problem with the CV joints. The best repair for this is to replace the CV half-shafts. The brake noise may or may not be related to this issue. If the noise is coming from the front, it could be that you need new brake pads, or that the rotors need to be resurfaced, or the brakes may need some other adjustment. If the noise is coming from the rear, you may need new brake shoes, or the drums need to be resurfaced, or there could be another issue. Have the brakes checked out when the CV axles are replaced.

If you need more help with these issues or if you have any more questions just let me know.