After an emergency stop the Brake Pedal wont push down

[mogwye]

Fabia 1.4 TDI.

 

After my wife had to make an emergency stop, the brake pedal will not push down or even attempt to apply the brakes.

 

Additional Info - Pedal will push down about 20-30 mm and applies a partial brake but not sufficient enough to stop the car

 

Anyone any ideas what to test before dismantling the braking system ?

 

DB.

Edited 24 November, 2016 by mogwye

[sepulchrave]

Test the ABS module with VCDS, run the bleed routine to see if it's operating correctly.

[petrolbloke]

The symptoms you describe are a slightly exaggerated version of what would happen if you lost vacuum to the brake booster. Without servo assistance the pedal will be very hard to push down and the brakes will feel very weak. Checking the pipes to the brake booster would be the first thing I'd look at.

Edited 24 November, 2016 by vrsTom

[sepulchrave]

Brakes would still work, you just have to push harder.

[mogwye]

Hi, thanks for your replies.

 

No fault codes logged.

 

On a 1.4 TDI - I have checked the vacuum pipe on the vac pump as OK, no splits, where exactly is the Servo unit located ? Any pics.

 

I have a Haynes manual but it's pics are pretty useless. 

 

DB.

[TMB]

The servo is what the brake fluid reservoir/master cylinder is attached to.

 

 

Edited 24 November, 2016 by TMB

[petrolbloke]

Brakes would still work, you just have to push harder.

As I said...

 

When a vac pipe split on mine I had to push the pedal ridiculously hard to even slow down gradually from 20mph - I can see how someone would think the brakes were not working at all.

 

Looks like the OP has edited his first post to confirm my thoughts!

 

OP: Servo should be easy to spot (big round black thing on the firewall driver's side). If you can't identify any issues with the pipes then try disconnecting it to see if it makes the pedal feel any different.

[fordfan]

Hold pressure on the brake pedal and start the engine, if the pedal does not drop, the servo isn't working correctly.

[mogwye]

Problem (hopefully) found - After inspecting both ends of the vacuum pipe from the pump to the servo I concluded all was OK, however on removing the air intake pipe to get a better view today, I was feeling around the non-return valve when it came away in my hand, the pipe on both sides of the NRV were split.

 

I attempted to cut & heat and push the pipe back on, but having tested for myself the total lack of braking caused by a split in the pipe, I decided to order a new complete pipe replacement on safety grounds.

 

With thanks to every one who contributed with answers.

 

DB.

[JWvrs25]

Problem (hopefully) found - After inspecting both ends of the vacuum pipe from the pump to the servo I concluded all was OK, however on removing the air intake pipe to get a better view today, I was feeling around the non-return valve when it came away in my hand, the pipe on both sides of the NRV were split.

 

I attempted to cut & heat and push the pipe back on, but having tested for myself the total lack of braking caused by a split in the pipe, I decided to order a new complete pipe replacement on safety grounds.

 

With thanks to every one who contributed with answers.

 

DB.

same thing happened to my car, only the pipe was only split in one location to the right of the NRV so i still had some braking

New pipe from skoda was £31.70 i think! 

[mogwye]

Mine cost £31.78 - Arriving Tuesday.

[JWvrs25]

cant understand why they are so expensive as just a rubber hose essentially.

 

Have fun trying to install the new hose. On mine i found the ends extremely tight fitting into the servo and the intake manifold, persistence and broken fingers paid off in the end

[mogwye]

Update - Fitted the new vacuum pipe today and the brakes are better than ever.

 

Thanks again for all your inputs.

 

DB.