Sprinter cdi brake fault

[mister_cee333]

Hi, can anyone help me with a problem i'm having with a 2002 sprinter 308cdi please?
When braking there is a "pulse" feeling through the brake pedal. I have checked all discs/pads etc (suspecting a warped disc) and can find no fault. The strange thing is that the "pulse" doesn't seem to vary it's tempo with the van road speed. I have recently purchased the van and it has been off the road for a few months. I have also towed the van with the engine off (but the ignition on) and the "pulse" is still there. Any help would be greatly appreciated as I'd like to solve the problem without the expense of a main dealer.
Thanks.

 

[clive williams]

Hi, can anyone help me with a problem i'm having with a 2002 sprinter 308cdi please?
When braking there is a "pulse" feeling through the brake pedal. I have checked all discs/pads etc (suspecting a warped disc) and can find no fault. The strange thing is that the "pulse" doesn't seem to vary it's tempo with the van road speed. I have recently purchased the van and it has been off the road for a few months. I have also towed the van with the engine off (but the ignition on) and the "pulse" is still there. Any help would be greatly appreciated as I'd like to solve the problem without the expense of a main dealer.
Thanks.

Hi mister,

How have you checked the discs/pads? Did you check the run out on the discs with a dial gauge? As the van's been off the road for a time another cause might be a partially siezed caliper piston. If so, then I would expect the offending disc to also overheat and maybe warp? as well as that caliper not working properly. Also, have you checked the rear face of the discs? If there is excessive corrosion in patches this can cause the same symptoms.
I would remove the pads, press the pistons back into the calipers and if you find a stiff piston push it in and out a few times to release it. Take care not to over-extend the piston and loose fluid.

Clive

500E
E320CDIT210

 

[guydewdney]

abs?

Try disconnecting the abs computer / abs fuse.. maybe the motor is 'running' when it shouldnt be.

actually unplug the abs unit (electrically) if you can (you may have to remove the cover for the plug)

Thats the only thing that I can think of that isnt engine related (as youi said its still there with engine off, being towed) AND isnt road speed related...

 

[mister_cee333]

Hi again,
I've got the problem solved. After further road testing it became clear that the "pulse" was indeed related to road speed, and could vaguely be felt through the steering. Therefore although the front discs looked in good condition I changed them and the pads. This has completely cured my problem.
Thanks for all your help. I hope I can be of assistance to other members now that I have found this forum.