SwedeSpeed - Volvo Performance Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
2,633 Posts
Discussion Starter · #1 ·
Not sure if this is normal or not, but after I come to a stop my brake pedal does sink a bit. Not to the point where I need to release and reapply the brakes or pump the brakes, but it sinks enough to feel it, feels like maybe 1/2 an inch to an inch. Should I be concerned? Coming up on a brake fluid replacement.

Also had an incident recently where I had to slam on my brakes suddenly then let up on the pedal but the brakes didn't seem to release? it was like the brake assist had a mind of its own. No messages yet.
 

·
Registered
Joined
·
1,242 Posts
I would bleed your brakes after a fluid replacement and see if that makes a difference. If that doesn't fix it I would check your calipers and see if a piston is sticking slightly and then releasing some after you are stopped.
 

·
Registered
Joined
·
1,692 Posts
Ever had the slave cylinder replaced? 2004 R surely didn't have the updated slave and that does run off of the same fluid and system. I would go ahead and do the fluid change and look at the calipers, valves, master cylinder, etc. See if you have any fluid loss or leaks while in there.

Not trying to freak you out, but remember reading that being a sign of a failing clutch slave when I had my R and it can be a pricey fix.
 

·
Registered
Joined
·
635 Posts
Ever had the slave cylinder replaced? 2004 R surely didn't have the updated slave and that does run off of the same fluid and system. I would go ahead and do the fluid change and look at the calipers, valves, master cylinder, etc. See if you have any fluid loss or leaks while in there.

Not trying to freak you out, but remember reading that being a sign of a failing clutch slave when I had my R and it can be a pricey fix.
Yep, if you have a manual, you're about to replace a leaky slave cylinder.
 

·
Registered
Joined
·
2,192 Posts
Not sure if this is normal or not, but after I come to a stop my brake pedal does sink a bit. Not to the point where I need to release and reapply the brakes or pump the brakes, but it sinks enough to feel it, feels like maybe 1/2 an inch to an inch. Should I be concerned? Coming up on a brake fluid replacement.

Also had an incident recently where I had to slam on my brakes suddenly then let up on the pedal but the brakes didn't seem to release? it was like the brake assist had a mind of its own. No messages yet.
How long has this been going on? If it just suddenly started happening it could mean that your slave cylinder has started leaking and you're brake fluid level is getting low, possibly low enough to allow air in the system without triggering a warning?

A friend of mine had weird brake pedal issues in his 2005 S80, turned out he just needed to replace the fluid and bleed the system.
 

·
Registered
Joined
·
1,674 Posts
If I understand the clutch/brake system correctly then the only component they share is the reservoir. Brakes go through the master cylinder and later through the Abs Pump, while the clutch goes through its own system. After swaping engine in my R, the master cylinder has gone south, however my clutch engagement was working fine. The brake pedal was sinking to the floor, while clutch was operating as it should. I would.start with brake bleeding, looking for leaks in the brake system and later , replace the master cylinder if needed. Sounds very similar to the issue I had.
 

·
Registered
Joined
·
2,633 Posts
Discussion Starter · #9 ·
Oddly enough, no missing fluid yet. No low brake fluid warnings. I'll have them bled and inspected when I get the fluid replaced.
 

·
Registered
Joined
·
1,674 Posts
Master cylinder leaks are usually internal, no fluid missing would indicate your problem if there is no air in the system.
 

·
Registered
Joined
·
121 Posts
I was experiencing the same issue too, some weeks later I got a Braking Fluid Low message and after that got DSTS problem message..
The problem was due to old brake pistons on front calipers! They were in terrible condition!
Replaced pistons and seals with VIVA kits, so everything is fine now!
 
1 - 12 of 12 Posts
Top