Please Can Somebody Help - Brake Problem.

[Surveyor]

Hello, am new to the forum, and am hoping a kind sole might be able to help me.

 

I have a 2005 1.9D Dispatch, its only done about 60k, I have personally only driven it for 2k.

 

Everything was fine with the van, then one day driving along, I went to brake, and it was literally like the engine had cut out, as there where no foot brake at all. I managed to safely stop, handbrake works fine.

 

Anyway, I put it down to my error or something, as seemed to work again fine. Next day, literally out of the blue, happened again. Not wanting to take the risk, I took van to garage.

 

They checked it, and said it was the master cylinder, as there where no leaks they could see etc. Anyway, master cylinder changed, a new caliper (as bleed nipple broke on old one) rear cylinder was changed as weeping).

 

I took the van back out, plodding along, bit nervous but seemed to be fine. Anyway, came up to a junction, applied the brakes, and there was nothing? So am totally stuck now, don't want to drive the van as don't want to risk an accident, but don't know what else it could be?

 

Please would anybody be kind enough to possibly shed some light. I bought the 1.9, as seemed to be a pritty straight forward no-nonsense type van, but am baffled and worried on what could be wrong.

[paul.h]

Welcome to the forum.

 

When the problem happens a bit more info is needed

- is the brake pedal going hard as if the vacuum servo is not working requiring excessive pressure on the pedal.

- is the pedal feel normal but no matter how hard you push the van does not slow down.

- is the brake pedal going all the way to the floor.

- when was the brake fluid last completely changed in case there is a high water level - should be changed every 2 years, if not the water in it can boil when braking hard so the brakes do not work.

- before you start the engine, if you push the brake pedal does it go down with vacuum still in the servo or is it hard straight away.

- if you push the brake pedal to remove the vacuum so it goes hard and then keep your foot on the brake pedal and then start the engine does the pedal go down a bit more as vacuum builds up in the servo.

- if you look under the dash at the brake pedal, when it is pushed is it working ok with no other movement/freeplay in the brackets/bulkhead.

- is the top of the brake fluid reservoir clean so that any vent hole on it is not blocked.

 

If the problem is due to a lack of vacuum it could be a servo leak, a problem with the non return valve on the vacuum hose to the servo, the vacuum pump may be faulty (look for any oil leaks and listen for any odd noises - it may be damaged where it connects to the end of the cam shaft), there might be a leak on the vacuum pipes or maybe an actuator that uses vacuum.

[Surveyor]

Hello Paul.h, thank you for your fantastic detailed response, I shall investigate all of the things listed.

 

So far, all the brake fluid has been changed, new master cylinder, caliper and rear brake piston, and has made no difference.

 

The fault is so random, can be braking fine, then just out of the blue with no warning, the foot brake just fails.

 

- When the ignition is off, I can press the pedal a few times, before it goes hard.

 

- I will check if it goes down anymore once ignition turned on.

 

- I don't think there's any leaks of oil on the system, as the garage did check the lines etc doing the other repairs.

 

- I wish I took more notice of how the pedal feels when it fails (but in blind panic in trying to stop, I just forget). best I can recall one one occasion, pedal did go down as normal, but there was no brake response? When it happens yesterday, I could have sworn the pedal went hard and there was very little travel?

 

Sorry, am not very technically savvy, and totally lost with the fault. Van otherwise drives fine, but I dare not take it to work in case it happens again.

[Surveyor]

Hi, I have pressed the pedal with engine off, and it gradually gets hard after a few pumps, until stiff. As I hold the pedal down, and start the van, it does go down.

 

Am just a bit lost with it all, just worried that it might happen at the worst moment.

 

I don't think my van being a 1.9D on a 2005 has any ABS etc, there's no warning lights on the dash.

 

Bit lost with it.

[paul.h]

It sounds as if the servo is ok but the pedal going hard when trying to brake suggests a vacuum problem. The pedal mechanism looks a bit complicated in the parts diagrams with levers, a connecting rod and the need for adjustment so maybe there  is something not right there.

 

To test the vacuum pump in the Haynes manual for the Xsara Picasso it says to connect a vacuum gauge to the hose from the pump and start the engine - it should reach at least 500 mmHg after 1 minute. If it does not reach this then the pump may be faulty. There is a topic here where the vacuum pump had failed http://www.citroen-owners-club.co.uk/citroen/topic/21810-a-little-worried-c15-van-vacuum-pump-knocking-noise-timing-belt/?hl= vacuum  pump

 

We could do with some input from other members but if there is nothing obvious I would take it to a Citroen dealer who should be familiar with the brakes.

 

On the back axle there is a brake compensator with a spring, if there are any odd spring noises these are known to cause it.

[Surveyor]

Hello Paul.h, thank you again, really appreciated.

 

I will get the vacuum part checked, am a bit short on funds, but they seem to be about £120 on eBay, then fitting.

 

I will keep you updated, thank you again.

[paul.h]

If it is the vacuum pump they only seem to be held on with 2 bolts, so I would think you could easily do this yourself.

 

To get the right part no. you can look at the Citroen parts diagrams if you register on service.citroen as another professional non emergency services and as a member fo the Citroen Owners Club. Once on the site use your VIN (VIS) top left to find your van and then the pump will be under Mechanical, Brakes and possibly Servo. You can then search on ebay using the part no. http://service.citroen.com/do/changerParametres you may need to select your language first.

[coastline taxis]

if your pedal is going hard and not stopping the car the id be checking the pads for signs of glazing.  if the pedal goes to the floor then check the slide mounts on the front calipers to see if they have siezed. also the self adjusters on the rear for the handbrake are very prone to failing and give the symptoms you describe.

 

Start by checking both front slidemounts as its free and will just cost you grease to put right

next check the padssee if the disc side is glazed.

 

then get back to us b4 the next stage