Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED

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Mon 29 Aug 2011 11:09
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - MZ62.0D

Hi All

I have a 2003 Diesel Mazda 6. At low revs the brake pedal goes rock hard which is cured by revving the engine a couple of times.

My local garage has already replaced the Master cylinder, Servo Unit and Vacuum Pump. There appears to be no problem with the brake lines or pads etc. My mechanic is stumped as am I

Any help or advice would be very much appreciated.

Thankk you.

Phil.

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Mon 29 Aug 2011 11:42
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - injection doc

it sounds very much like a loss of vacum. There should be a seal between the M/Cyl and the servo. Need to check the seal. I would also check the servo pipe for air leaks and the fitted check valve. If the check valve has failed then the vacum will be lost at idle.

Some garages have an ultrasonic sound detector that can listen for the tiniest of air leaks, these are very good but very few iether use them or know how too ! but ideal for this sort of fault.

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Mon 29 Aug 2011 12:51
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - Peter D

You say it is a desiel engine so it has a vacuum pump. If as Injection doc has stated, you need to check the seal and the vacuum pipes but you may need to check the pump, they fo fail. Regards Peter

Edited by Peter D on 29/08/2011 at 12:51

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Mon 29 Aug 2011 14:00
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - MZ62.0D

Thanks a million for that - will see if the problem can be solved. Appreciate the fast answer.

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Thu 22 Sep 2011 16:12
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - Daniel Johnston

Hi Mate,

I have had the exact same problem since January. After 2 servo's, 4 vacuum pumps and a master cylinder, my mechanic has found that due to a lack of oil changes by the previous owner, there was a blockage somewhere in the top end of the engine, preventing oil from getting to the vacuum pump. He flushed and changed the oil 4 or 5 times and had no luck, so we gave up and I arranged to meet him so I could collect my car. Just before he set off he did another oil change and loads of gunk was removed from the engine, he then manually drip fed oil to the vac pump and hey presto, brakes are now working. I have just been told to monitor oil levels and drip feed oil to the vac pump every 2-3 days. If I was you, I would try manually feeding oil to the vacuum pump. If this works, you know you have a blockage somewhere.

Email me on daniel.johnston@lomature.com and I can give you help on how to do this.

Regards,

Dan.

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Fri 23 Sep 2011 05:11
Mazda 6 - Mazda 6 - Brake Problem MECHANIC STUMPED - gordonbennet

Vacuum pipe possibly collapsing.

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