Intermittent brakes and effects rpm's?
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Intermittent brakes and effects rpm's?
I have a weird issue with the braking system in my '95 civic ex. The brakes will sometimes almost go full stroke and not stop the car unless u pump them up. They aren't spongy and the master cylinder has been replaced. Yes, they have been bled off and no change in the hydraulic fluid level. To make matters worse, yesterday when i stopped by the garage, I was pumping the brakes and the rpm's went up until i stopped, then came back dn. What's up with that? Any ideas or has anyone run into this problem before?
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Re: Intermittent brakes and effects rpm's?
I was pumping the brakes and the rpm's went up until i stopped, then came back dn. What's up with that?
Can't say anything about the rest of your story though.
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The booster operates using manifold vacuum.
You repeatedly pumping the brake pedal causes the same effect as a vacuum leak....until you quit pumping it.
You repeatedly pumping the brake pedal causes the same effect as a vacuum leak....until you quit pumping it.
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8/9th gen are the 2006-2015 cars. Also, you have a question, not a helpful DIY article. moved to right generation/out of the DIY section.
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Rep Power: 518 Re: Intermittent brakes and effects rpm's?
The brakes will sometimes almost go full stroke
Assuming this is true....
Take it to loose gravel and do this, stab the pedal once and make the car skid using the 2 wheels that still have working brakes. Get out and see which wheels made skid marks.
The 2 wheels that did not make skid marks are the ones that have the problem.
If you can get this far, you've narrowed the problem area by half.
yesterday when i stopped by the garage,
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If you stand on the brake pedal without pumping, is there any braking action at all?
Assuming this is true....
Take it to loose gravel and do this, stab the pedal once and make the car skid using the 2 wheels that still have working brakes. Get out and see which wheels made skid marks.
The 2 wheels that did not make skid marks are the ones that have the problem.
If you can get this far, you've narrowed the problem area by half.
What does your mechanic say about this?
Assuming this is true....
Take it to loose gravel and do this, stab the pedal once and make the car skid using the 2 wheels that still have working brakes. Get out and see which wheels made skid marks.
The 2 wheels that did not make skid marks are the ones that have the problem.
If you can get this far, you've narrowed the problem area by half.
What does your mechanic say about this?
If you think a good mechanic is expensive, try hiring a bad one
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From: Midwest. Aiming about mid-chest
Rep Power: 518 Re: Intermittent brakes and effects rpm's?
So the front brakes work.....rears must be the problem?
Have you removed the brake drums to inspect?
Have you removed the brake drums to inspect?
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Rep Power: 228 Re: Intermittent brakes and effects rpm's?
no abs means that the braking system is down to
master cylinder (if it was bad you would have brakes but they wouldn't be power assisted, so that should be fine)
proportioning valve: (could be leaking, but probably wouldn't cause intermittent issue)
brake lines (you would probably have no pressure very soon if one of these were blown)
front:
rotors (would not effect brake pedal travel)
pads (would not cause intermittent brake pedal travel)
calipers ***if leaking could cause issue, possible loose bleeder bolts***
rear:
drum pistons ***could cause intermittent pressure loss if seals are blown***
drum brake pads
drum cover (would not cause issue)
Pull off your front tires and look for leaks
then If you find nothing pull for the rear drum covers and look for leaks
(my guess rear drum pads are so worn that the rear pistons have slipped past their gaskets and are causing intermittent pressure lose while braking hard/ rear pistons are done and should be replaced if rear pad depth is thick)
master cylinder (if it was bad you would have brakes but they wouldn't be power assisted, so that should be fine)
proportioning valve: (could be leaking, but probably wouldn't cause intermittent issue)
brake lines (you would probably have no pressure very soon if one of these were blown)
front:
rotors (would not effect brake pedal travel)
pads (would not cause intermittent brake pedal travel)
calipers ***if leaking could cause issue, possible loose bleeder bolts***
rear:
drum pistons ***could cause intermittent pressure loss if seals are blown***
drum brake pads
drum cover (would not cause issue)
Pull off your front tires and look for leaks
then If you find nothing pull for the rear drum covers and look for leaks
(my guess rear drum pads are so worn that the rear pistons have slipped past their gaskets and are causing intermittent pressure lose while braking hard/ rear pistons are done and should be replaced if rear pad depth is thick)
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no abs means that the braking system is down to
master cylinder (if it was bad you would have brakes but they wouldn't be power assisted, so that should be fine)
proportioning valve: (could be leaking, but probably wouldn't cause intermittent issue)
brake lines (you would probably have no pressure very soon if one of these were blown)
front:
rotors (would not effect brake pedal travel)
pads (would not cause intermittent brake pedal travel)
calipers ***if leaking could cause issue, possible loose bleeder bolts***
rear:
drum pistons ***could cause intermittent pressure loss if seals are blown***
drum brake pads
drum cover (would not cause issue)
Pull off your front tires and look for leaks
then If you find nothing pull for the rear drum covers and look for leaks
(my guess rear drum pads are so worn that the rear pistons have slipped past their gaskets and are causing intermittent pressure lose while braking hard/ rear pistons are done and should be replaced if rear pad depth is thick)
master cylinder (if it was bad you would have brakes but they wouldn't be power assisted, so that should be fine)
proportioning valve: (could be leaking, but probably wouldn't cause intermittent issue)
brake lines (you would probably have no pressure very soon if one of these were blown)
front:
rotors (would not effect brake pedal travel)
pads (would not cause intermittent brake pedal travel)
calipers ***if leaking could cause issue, possible loose bleeder bolts***
rear:
drum pistons ***could cause intermittent pressure loss if seals are blown***
drum brake pads
drum cover (would not cause issue)
Pull off your front tires and look for leaks
then If you find nothing pull for the rear drum covers and look for leaks
(my guess rear drum pads are so worn that the rear pistons have slipped past their gaskets and are causing intermittent pressure lose while braking hard/ rear pistons are done and should be replaced if rear pad depth is thick)
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From: Midwest. Aiming about mid-chest
Rep Power: 518 Re: Intermittent brakes and effects rpm's?
Outside tire receives that weight, which increases traction and keeps it turning.
You were supposed to try that skid in gravel going in a straight line.
What about the rears?
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Straight line, they act normal and so does the brake pedal. Only when turning sharp does this occur, with the wheel locking up and brake pedal going full stroke. Rears seem to be just fine.
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From: Midwest. Aiming about mid-chest
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How about.....If you sloooowly push the pedal down does it go to the floor?
And if you stab the pedal quick the brakes feel normal?
And if you stab the pedal quick the brakes feel normal?
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