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General Information => Troubleshooting => Topic started by: Mopar44o on January 02, 2009, 11:31:10 am

Title: Brakes no pressure....
Post by: Mopar44o on January 02, 2009, 11:31:10 am

If I try the brakes with the car off they are fine and hold preasure, this only happens when its running.

Ok so it started with the brakes loosing preasure while holding the pedal once in a while....  But now the pedal has virtually no preasure. It goes right to the floor and slowly stops the car. I can pump it up a bit but then it looses the preasure again.

I'm gonna bring it to my mechanic on monday... But he said (before it was completly loosing preasure) that it sounded like they might need some adjustment. What do you guys think is wrong?

Title: Brakes no pressure....
Post by: AndrewSE on January 02, 2009, 11:36:09 am

Almost the same problem with my 91 jetta.

Was my master cylinder that was the issue.

Title: Brakes no pressure....
Post by: burn_your_money on January 02, 2009, 06:42:06 pm

Check for leaks in the entire brake system. If there aren't any, then the master cylinder is the most likely suspect

Title: Brakes no pressure....
Post by: Mopar44o on January 03, 2009, 09:06:01 am

Would it hold preassure with the car off if it was the master cylinder?

Title: Brakes no pressure....
Post by: smutts on January 05, 2009, 02:14:20 pm

You will be compressing a load of air instead of vacuum. Dive onto an inflated air matress, then an empty one to feel the difference.  :wink:
 
This will resist the pedal, start engine and this will fall to the floor. If the master cylinder has died, a few pints of excellent paint stripper lurks in the servo waiting for you to tip it all over the paintwork. :lol:
 
The vacuum pump will also have been pumping this into the crankcase, so budget for an oil change too. :?