Hard pedal when engine off.Spongy when running.Air in lines?
Discussion
Maybe a very silly question.
Golf mk4 1.8t.
Had to change the rear near side solid brake line from the under beam flexi to caliper.
Bleed nipple threads within caliper borked so new Pagid item now on.
Bled with the old man. In, out, in, out.......no more bubbles in the line.
Pedal is rock solid with the engine off. Tis a little spongy with the engine running.
Does this point to air being in the line, or a servo issue?
Pump the pedal a few times when it's running and it's nice and firm for one pedal, then it's back to being a little spongy.
Golf mk4 1.8t.
Had to change the rear near side solid brake line from the under beam flexi to caliper.
Bleed nipple threads within caliper borked so new Pagid item now on.
Bled with the old man. In, out, in, out.......no more bubbles in the line.
Pedal is rock solid with the engine off. Tis a little spongy with the engine running.
Does this point to air being in the line, or a servo issue?
Pump the pedal a few times when it's running and it's nice and firm for one pedal, then it's back to being a little spongy.
Your car has a brake servo, with a large Master cylinder, so that the travel is minimal, but with no engine vacuum it needs a massive pedal pressure.
That's what you feel with the engine off.
With it on you have servo assistance, and can sense the residual bubbles.
Bleed it again. And again, if needed!
Always bleed first the brake furthest from the master cylinder. Not sure which rear brake that is on your Golf. Check, by looking at the run of the brake lines.
John
That's what you feel with the engine off.
With it on you have servo assistance, and can sense the residual bubbles.
Bleed it again. And again, if needed!
Always bleed first the brake furthest from the master cylinder. Not sure which rear brake that is on your Golf. Check, by looking at the run of the brake lines.
John
An older car with a lot of servo you might expect a bit of creep if you're standing on it. If it's creeping all the way to the floor with light/moderate pressure then the master cylinder is knobbled
If you've replaced lines you may have introduced a bit of air into the ABS block (although less likely for a short section at the rear). Try going out and standing on the brakes a few times then re-bleed thoroughly, you might find a bit more air.
If you've replaced lines you may have introduced a bit of air into the ABS block (although less likely for a short section at the rear). Try going out and standing on the brakes a few times then re-bleed thoroughly, you might find a bit more air.
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