Anyone able to help stop my car!

2003 tdi 100.

I suspect it may be related to the vacuum pump - symptom is hard pedal under sudden firm braking. Performance is normally progressive and sharp, but seems to become heavy in these circumstances. It seems intermittent but I don't feel like I can always rely on them.

There are no fluid leaks, sticking calipers or vaccuam hose leaks that I can find and I don't think it could be related to the modulator???

Advice appreciated.

Hi, 2004 1.4 TDI.

I had this a few times in the first years of the car's life. Quite frightening. Couldn't find anything wrong, but the cover on the 'little box' into which the vacuum pipes go (driver's side near scuttle) was loose. Fastened this tightly closed with springs. Haven't had any problems since. Don't know why this should make a difference as it doesn't seem to work on the 'active' side of the braking system. Maybe coincidence, but worth having a look. Please feedback here. There was a thread a while back where a Briskodian seemed to have the same problem leading to a shunt. Police garage found nothing wrong with brakes.

A very hard, and heavy, pedal sounds like you're dumping vacumn somehow or other.

similar problem here on my polo 100pd :(

it needed new discs and pads anyway so they were changed but pedal needs to be pressed HARD for the car to stop.

I have checked:

discs

pads

callipers

lines and hoses

all seem fine so it must be a servo related issue.

I had similar problems with my Passat 1.9 TDi. Found a blanking cap on the main vacuum pipe to the servo was not sealing correctly. Replaced with a hose with a bolt in and now seems to hold vacuum better and brakes seem consistent at last! My turbo is also working better now it is getting full vacuum for the VNT!

If you are in/near the West Midlands or near Coventry, I have a vacuum tester and could do a quick check for you.......

Fabby,

Could you please give a bit more detail? Where is the blanking cap and where are you connecting the gauge to test the vacuum?

Many thanks

V