[bro67]

does anyone know how to bleed the brakes on an audi a4 1997 have just changed discs and brake pads now i dont have any brakes it was the back brakes i did already did the front ones with no problems :liebe011:

 

[volcanoblack]

Changing the rotors and pads does not normally require bleeding the brakes since no air would be allowed into the system. You may want to look elsewhere for a problem. You might also clarify, when you say no brakes. Do you see a pool of brake fluid on the ground? Do you really mean no brakes, or do you have to pump the pedal, or is it just that the car does not stop as quickly as it did before the brake work?

VB

 

[bro67]

had bother to begin with putting the pistons back into the caliper havent noticed any brake fluid the pedal is nearly touching the floor before you get any brakes :liebe011 :the brake light and abs light is also on :liebe011:

 

[volcanoblack]

The rear brakes on the Audi have a piston that must be turned at the same time as being pushed back into the bore. It takes a special tool - available at most auto parts stores, online and elsewhere.

Assuiming you got the piston back into the bore without some physical damage, then you should have good brakes after pushing the pedal a few times to get the pads against the rotors.

For bleeding the brakes I would recommend getting a power bleeder (you might be able to rent one) and flush the system at the same time as bleeding. The pressure bleeder attaches to the master cylinder. Then at each wheel use a plastic hose just big enough to fit over the bleed screw. The plastic tube should be about 12" - 18" long and connected to another plastic bottle to catch all the drained fluid. The bottle must be above the bleed screw so that any air bubbles that do come out go up to the bottle and not back into the brakes.

Loosen the bleed screw just enough to get a good flow but not too loose so that air can sneak back in around the threads. Takes a few miunutes at each wheel to flush the system. You will need several pints to do all four calipers.

Good luck with finding your problem. And use a really, really good brake fluid - not the cheap stuff at WalMart.

Here are some:

MotulRBF600 (DOT 4)
Motul 5.1 (DOT 5.1)
ATE Super Blue (DOT 4)
ATE SL (OEM) (DOT 4)

VB

 

[bro67]

i now have brakes .system was bled again and they work fine,,,,,,,,,however now the abs light is on,new discs,pads and rotors were fitted,thought the problem might be the rotors so tonite the old rotors were fitted,still no joy,does the abs have to be reset by any other means than disconnecting the battery for a few mins?..a diagnostic was run and that determined that there was no problem with the sensors,tech said the back wheels were showing the abs fault hence the rotor change.