Break problems and lack of power.

[David Carkett]

Hi everybody,

A little advice is required please. My breaks are working, but every now and the the brake pedal drops slightly when being pressed, then returns to normal.
(i know it is men t to go down when pushed)

It feels like air in the system, but it doesn't happen all the time.

No ABS light, break fluid is fine, any suggestions??

Also I lost power from the engine, it kept running but 1st 2nd OK. 3, 4,5 there was no power. It wasn't limp mode, but like only 30 bhp. any link?
Turned off, restarted and has been fine ever since?

Most confusing.
:confused:

[caldirun]

Hi everybody,

A little advice is required please. My breaks are working, but every now and the the brake pedal drops slightly when being pressed, then returns to normal.
(i know it is men t to go down when pushed)

It feels like air in the system, but it doesn't happen all the time.

No ABS light, break fluid is fine, any suggestions??

Also I lost power from the engine, it kept running but 1st 2nd OK. 3, 4,5 there was no power. It wasn't limp mode, but like only 30 bhp. any link?
Turned off, restarted and has been fine ever since?

Most confusing.
:confused:
Possibly a vacuum system fault.

[iwaters]

^^^What he said. Sounds like a vac leak, check all hoses carefully for splits and cracks.

[elanman]

Petrol or diesel?

[David Carkett]

1.9td 130bhp diesel.

[martin1810]

Faulty servo, tandem pump fault, one way valve fault in vacuum lines or vacuum line fault. You need someone to check the vacuum lines for you with a vacuum pump.

[David Carkett]

Thanks,
So where is the tandem pump? and where do i find a vacuum pump?
Am i looking at a trip to a garage?

thanks

[ddraig]

I have heared of this before, a friend had similar problems, it turned out believe it or not to just be the brake switch under the pedal at fault, apparently its monitored by the engine managment and can cause low power or limp mode, hope this helps.

[TechTricks]

Hi all, I have a 1998 Alhambra 1.9 TDi 95bhp, last weekend, i started the car while worm, the engine started and surged, never don it before, while driving, it's lost power. since Ive had the car Ive notice more often than not while releasing the break peddle quickly I can hear the vacuum leaking from under the dash, also a while back I noticed the recirculate switch stopped working, never thought anything of it, does anyone know if these are all connected? I read a early a post that their is some sort of vacume pump is this the case?
Thanks for any help
Graham

[martin1810]

All diesel engines have a vacuum pump to power vacuum systems like brakes, turbo etc.
A diesel engine can't develope vacuum like a petrol engine does. The 1.9 tdi vacuum pump is on the end of the cylinderhead. It is a combined fuel and vavuum pump called a tandem pump. You may be hearing the servo. How do the brakes feel. A code read is the best place to start.