daveywoods - Problem With Brakes

[daveywoods]

rover 75 connysue 2.0 cdti 2004 model estate.
I have a brake problem. at start up there is very poor braking, almost none. after reving engine for about a minute and when driving brakes are o.k. not brilliant but adequate although pedal travel seems longer than usual. any ideas anyone ?

[Reebs]

I've expanded your thread title to illustrate the subject matter Davey. I'm sure someone will be along shortly with an answer :}

[Mike Noc]

rover 75 connysue 2.0 cdti 2004 model estate.
I have a brake problem. at start up there is very poor braking, almost none. after reving engine for about a minute and when driving brakes are o.k. not brilliant but adequate although pedal travel seems longer than usual. any ideas anyone ?

Dave is the pedal hard when you start up? If so then you could have a vacuum leak which is affecting the servo assist for the brakes.

Check all the pipework. The vacuum pump is driven off the rear of one of the camshafts and is on the nearside top of the engine inward of the battery.

The pipes go to the brake servo on the off side in the plenum chamber, and also to the EGR valve at the front of the engine on the near side via the EGR control valve which sits under by the starter motor. Not easy to see the pipes around that area, but they can wear through due to vibration if rubbing against anything.

[oldcarguy]

Sounds like a servo problem, with the engine off, pump the brake pedal a few times to clear the system, and then start the engine with your foot on the brake pedal, you should feel it drop an inch or two.

[daveywoods]

re poor brakes, car is in local garage at the moment.they are normally pretty good but seem a bit baffled by this one . system has been bled for air , vacuum hoses checked. they are now talking about the master cylinder. if that is the fault surely the brakes wouldn't work properly when travelling. also as engine is made by BMW. can anyone tell me if BMW engine spares are compatible. such as vacuum pump??

[Mike Noc]

Vacuum pumps are normally bullet proof, so don't let the garage start changing stuff without diagnosing the system properly first, or it will get expensive.

Get them to pull the pipe off and check the vacuum at the pump, then reconnect and do the same at the brake servo. If they don't get the same amount of vacuum then get them to trace the pipes to the EGR.

As I mentioned these are hidden where they go to the front of the engine and can split due to the vibration.

[daveywoods]

Re: 75 Brake problems. Brakes working fine now. after checking the system pipes etc. Local garage changed master cylinder many thanks to Mike Noc and Old Car Guy for their advice.