C4 brakes question
Thread Starter
Drifting
Joined: Aug 2001
Posts: 1,823
Likes: 1
From: Arlington TN
C4 brakes question
I know I've asked here before, but thought I would try to seek some clarification.
As my brakes have been (conservatively) used up, I have noticed that I have to keep adding small amounts of brake fluid to the resivoir. Otherwise, if I do have to actually get on the brakes, I will get the Service ASR/Service ABS lights on.
This seemed to only be a once a month thing.....Adding the brake fluid (usually only a tablespoon or two max) makes the problem go away (doesnt trigger a brake code).
But - over the past month, Ive had to add fluid twice, and although I am not measuring, I'd say that it was more than the normal tablespoon or two. I have looked all around the master cylinder, around the calipers/connectors, and I can find no evidence of a leak. No spots on the garage floor, nothing!
Is there some other place I should look for a possible leak? Say back in the ABS module (I'm not sure if hydraulics even goes to that part or whether it is only electrical) Or, is this simply normal and the frequency of needing fluid increases as the pads get worn closer to the end? (This is my first cycle of brake pads).
Also - the brakes themselves have always felt fine - i.e. not squishy, pedal isnt going to the floor. Pedal is always firm.
Just seems that darn sensor that triggers the Service ABS/ASR is awfully touchy.
Thanks in advance for any advice.
--car is a 93, with stock (12 inch :() brakes--
As my brakes have been (conservatively) used up, I have noticed that I have to keep adding small amounts of brake fluid to the resivoir. Otherwise, if I do have to actually get on the brakes, I will get the Service ASR/Service ABS lights on.
This seemed to only be a once a month thing.....Adding the brake fluid (usually only a tablespoon or two max) makes the problem go away (doesnt trigger a brake code).
But - over the past month, Ive had to add fluid twice, and although I am not measuring, I'd say that it was more than the normal tablespoon or two. I have looked all around the master cylinder, around the calipers/connectors, and I can find no evidence of a leak. No spots on the garage floor, nothing!
Is there some other place I should look for a possible leak? Say back in the ABS module (I'm not sure if hydraulics even goes to that part or whether it is only electrical) Or, is this simply normal and the frequency of needing fluid increases as the pads get worn closer to the end? (This is my first cycle of brake pads).
Also - the brakes themselves have always felt fine - i.e. not squishy, pedal isnt going to the floor. Pedal is always firm.
Just seems that darn sensor that triggers the Service ABS/ASR is awfully touchy.
Thanks in advance for any advice.
--car is a 93, with stock (12 inch :() brakes--
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Re: C4 brakes question (BrentDev)
The ABS/ASR pump and module are behind the driver's seat. Remove the screw holding the lid down and look all around for indications of moisture areound the fittings. That stuff is pretty expensive to replace so hope for only a leak at one of the fittings.
It doesn't take a lot for the Service ABS/ASR light to come on. The master cylinder being down about 3/16 inch from the full mark will cause that. The sloshing of the fluid in the cylinder uncovers the sensor.
How about the rubber hoses themselves? Dry?? Did you look for any indications of fluid around the caliper pistons and/or the dust seals on the inside pads?
If the pads are really thin, the fluid will be drawn into the caliper pistons but the amount would be small and you would only have to top off the reservoir once to replace the amount displaced by the increased piston travel from wear.
It doesn't take a lot for the Service ABS/ASR light to come on. The master cylinder being down about 3/16 inch from the full mark will cause that. The sloshing of the fluid in the cylinder uncovers the sensor.
How about the rubber hoses themselves? Dry?? Did you look for any indications of fluid around the caliper pistons and/or the dust seals on the inside pads?
If the pads are really thin, the fluid will be drawn into the caliper pistons but the amount would be small and you would only have to top off the reservoir once to replace the amount displaced by the increased piston travel from wear.
Thread Starter
Drifting
Joined: Aug 2001
Posts: 1,823
Likes: 1
From: Arlington TN
Re: C4 brakes question (c4cruiser)
thanks for the reply.
No - my visual inspection has not included actually poping the pin off the calipers. Hoses and fittings all look good. Better go look back in the ABS lockbox.
No - my visual inspection has not included actually poping the pin off the calipers. Hoses and fittings all look good. Better go look back in the ABS lockbox.
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Re: C4 brakes question (BrentDev)
I know I've asked here before, but thought I would try to seek some clarification.
As my brakes have been (conservatively) used up, I have noticed that I have to keep adding small amounts of brake fluid to the resivoir. Otherwise, if I do have to actually get on the brakes, I will get the Service ASR/Service ABS lights on.
This seemed to only be a once a month thing.....Adding the brake fluid (usually only a tablespoon or two max) makes the problem go away (doesnt trigger a brake code).
But - over the past month, Ive had to add fluid twice, and although I am not measuring, I'd say that it was more than the normal tablespoon or two. I have looked all around the master cylinder, around the calipers/connectors, and I can find no evidence of a leak. No spots on the garage floor, nothing!
Is there some other place I should look for a possible leak? Say back in the ABS module (I'm not sure if hydraulics even goes to that part or whether it is only electrical) Or, is this simply normal and the frequency of needing fluid increases as the pads get worn closer to the end? (This is my first cycle of brake pads).
Also - the brakes themselves have always felt fine - i.e. not squishy, pedal isnt going to the floor. Pedal is always firm.
Just seems that darn sensor that triggers the Service ABS/ASR is awfully touchy.
Thanks in advance for any advice.
--car is a 93, with stock (12 inch :() brakes--
As my brakes have been (conservatively) used up, I have noticed that I have to keep adding small amounts of brake fluid to the resivoir. Otherwise, if I do have to actually get on the brakes, I will get the Service ASR/Service ABS lights on.
This seemed to only be a once a month thing.....Adding the brake fluid (usually only a tablespoon or two max) makes the problem go away (doesnt trigger a brake code).
But - over the past month, Ive had to add fluid twice, and although I am not measuring, I'd say that it was more than the normal tablespoon or two. I have looked all around the master cylinder, around the calipers/connectors, and I can find no evidence of a leak. No spots on the garage floor, nothing!
Is there some other place I should look for a possible leak? Say back in the ABS module (I'm not sure if hydraulics even goes to that part or whether it is only electrical) Or, is this simply normal and the frequency of needing fluid increases as the pads get worn closer to the end? (This is my first cycle of brake pads).
Also - the brakes themselves have always felt fine - i.e. not squishy, pedal isnt going to the floor. Pedal is always firm.
Just seems that darn sensor that triggers the Service ABS/ASR is awfully touchy.
Thanks in advance for any advice.
--car is a 93, with stock (12 inch :() brakes--
The amount of brake fluid you have been adding seems like much more than you would need to compensate for pad wear. And IMHO, the level in the master cylinder, unless it is below the MIN line, shouldn't set off any signals or codes unless there is a problem elsewhere.
Just my $0.02
:steering: [ I love that Lil Guy! ]
