Air on one injector....(Bosch VE)

[darrenjlobb]

Hey guys..

I have a bit of a problem, Was basically driving my car, everything was fine, then i started getting a loud knocking nice, in time with the revs....wasnt sure what to think at the time, but after further investigation, turns out that one, of the four delivery valves on the pump is putting out air, the other 3 are firing normally, but just this one is putting out air and next to no diesel, hence building pressure in the line and randomly half injecting..

What on earth has caused this, its a pump i built with a bigger head and govmod...

Have i cracked the pump head?

Thanks..

[Mark(The Miser)UK]

Hi,
How do you know it's putting out air?

Did you disconnect the lines at the delivery valve end, and  find one was putting out next to nothing?

Could it be that the delivery valve is not seating properly and so not sealing between strokes?

Maybe....
Try swapping bad D/V to another line nd see if problem moves

[darrenjlobb]

Turned out to be stuck injector putting air back from the cylinders !