Ford Mondeo II (1996 - 2000) - 1998 2.0 Loss of braking while driving?

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Mon 3 Nov 2008 08:47
1998 2.0 Loss of braking while driving? - Saints best kept secret
Good morning all,
I had a major problem last night. Iwas driving back from Legoland to Southampton and I started hearing a "suction noise" while accelerating? Only when accelerating.
Monitored warning lights, temperature etc but everything here seemed to be ok.
Did seem to lose power but thought I'd just be very careful and stick to 60mph.
Didn't realise until I got to M27 slip road that I had NO BRAKES! Pedal wouldn't move and brkaes as good as useless. Very scary and somehow we got home (crawling and being extremely careful!)
Started car this morning and its idling is very rough which is new.
I have checked the brake fluid reservoir which is ok and the hose on this and the black cylinder behing it seem to be connected?
Can anyone give me any advice on what it could be and a possible fix?
Thanks to all for reading and sorry fo long post just wanted to try and cover everything.
Chris.

Edited by Saints best kept secret on 03/11/2008 at 08:48

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Mon 3 Nov 2008 08:58
1998 2.0 Loss of braking while driving? - L'escargot
Sounds like a leak/disconnection in the vacuum pipe to the brake servo, or in the servo itself.

Edited by L'escargot on 03/11/2008 at 09:01

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Mon 3 Nov 2008 10:06
1998 2.0 Loss of braking while driving? - Peter D
It sounds like the Brake servo has either correoded through due to bloked drain holes and the plenum chamber is retaining water or a pipe has failed. The former is not uncommon. thus the sucking noise and the loss of brakes, well at lease the servo assisted part. Regards Peter
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Mon 3 Nov 2008 10:09
1998 2.0 Loss of braking while driving? - Peter D
Sorry I was in Audi mode, but still sounds like a failed diaphragm or pipework. If the sucking noise was inside the car then the servo has failed. Regards Peter
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Wed 5 Nov 2008 13:40
1998 2.0 Loss of braking while driving? - Saints best kept secret
Thanks for the replies.
The suction noise is definitely audible inside the car.
All pipes are ok.
I have looked around and if you "fiddle" with the bellows on the back of the servo it makes a difference so I am presuming the servo unit needs replacing.
Please excuse my ignorance but I'm not a mechanic,
it looks as though I can unbolt the master sylinder from the servo,
Unbolt the servo from the bulkhead,
disconnect wire from servo,
undo brake pedal from servo,
take out servo then do again in reverse to fit a new one?
Is there anything I am missing or should be aware of?
Any handy tips to make things simple?
Any and all advice greatly appreciated.
Thanks once again.
Chris.
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Wed 5 Nov 2008 14:16
1998 2.0 Loss of braking while driving? - Peter D
You may have to break into the braking circuit to get the master cylinder out of the way. This is the braking circuit and safety is at stake here. If you have not done type of job before then this be ajob for a good mech. Regards Peter
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Wed 5 Nov 2008 14:55
1998 2.0 Loss of braking while driving? - Saints best kept secret
I did think that might be the answer!
Just didn't fancy having to get it towed to the garage as I can't drive it there.
I know an ex mechanic but didn't really want to bother him, guess I'll need some beer money for him!
Thanks once again for all your help and advice, I really appreciate it.
All the best.
Chris.
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