EAS again and again i know!

Hi i have just changed all air springs today due to the originals been perished in the usual place. I replaced them due to the car sinking now i have only just changed them no leaks so far i have also rebuilt the compressor with new seal and cylinder. eas raises and works fine. But here is the big but when i switch the engine off all of the air from the tank vents out of the exhaust this only happens when ignition off i have previously rebuilt this valve block which i bought s/hand and then rebuilt i am thinking of overhauling the original valve block. Does any one have any thoughts on why it bleeds all of the air off when ign off? thanks in advance.

have you looked at the faults recorded? maybe theres:

a, a leak

b, the exhaust valve is stuck? could the wires be on wrong (long shot) telling it to open instead of close?

does the pump run all the time?

Cheers gav but when ign is on the system seems to work ok pump kicks in and out as expected i'm thinking one of the non return valves is sticking maybe got **** in it as the compressor cylinder was well worn ordered a rebuild kit for my old valve block and see how it goes thanks Andy