Hard pedal when engine off.Spongy when running.Air in lines?

[paultownsend]

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.

[paultownsend]

So why does this not happen when the engine is off.
Rock hard when engine is off. Surely if there is air in a line, the pedal will sink?

[paultownsend]

Gave that line another bleed. A single bubble came out and I bled the m/c.
A little better.
Now back to the servo. Should the pedal sink slowly to the floor when the engine is on. Or does that still mean air in the line, somewhere......

[paultownsend]

All sorted! Bled all 4 lines, clutch and M/c!

Now, the aircon has broken! New condenser time.....

[paultownsend]

All sorted! Bled all 4 lines, clutch and M/c!

Now, the aircon has broken! New condenser time.....