17 replies to this topic

[Coene614]

You may still need a manifold vacuum reading without the servo connected as a reference. We don't know if -0.6 bar is max vacuum or if there is a small leak.   

Simple video here of how a servo works and internal valves inside the servo that allow airflow at different points

https://www.google.c...bTUvp-tD5M,st:0

 

I checked manifold vacuum its also -0.6 bar, also checked the non return valve and it works perfectly. Then i tried to test the servo and i coulnd't get it below -0.5 by using the vacuum hand pump i got, vacuum would also decrease from -0.5 to -0.3 in about a minute or 2. 

[Earwax]

Another possibility similar to what absx2 describes ( again highly unlikely but can have sinister outcomes ) is a hairline fracture of the CV, or maybe even the split washer creating movement similar to collapsing bearing. I too think it is vacuum related but it is not the sort of thing you want to magically disappear ( or irregularly disappear) without knowing WHY.   

[lsto]

Have you checked the rubber hoses. It's uncommon but I have seen a brake pipe bulge when you push the brake pedal. Brakes still work but you have extra travel as the hose bulges out under pressure then shrinks back when you take your foot off the brake.