Back to looking at vacuum as possible cause of poor running and starting

 

Octavia2 1.9 PD BXE

 

Can't detect any leaks but notice that with engine idling 12 very quick stabs at brake pedal leads to firm pedal suggesting loss of vacuum assist. Only takes 1 to 2 seconds for pedal to return top normal feel.

 

I am thinking this means that pump is unable to keep up with vacuum demand either due to poor pump performance or leak.

 

I would add though that I have had no problem with lack of servo assist in normal driving

 

When I switched the engine off after this repeated brake application today the solenoid valve block buzzed for about 1 min 30s.

 

In normal use I do sometimes get this buzz but not most times not and never for this long.

 

Most times when I return to car after even some time there is still vacuum assist available (soft pedal) before running engine on rare occasions pedal is firm (no servo assist I assume) until engine is running.

 

Any thoughts on whether some or all of the above is normal or if not what it points to?

 

I do not have access to a fully functioning similar car for comparison

 

Thanks

 

Sounds normal to me, you can easily pump out the servo.

Sounds normal to me, you can easily pump out the servo.

Thanks - thought that might be the case (particularly given how small the vacuum reservoir is), but good to get that confirmed.