Originally Posted by
FLvector
+1 The only issue I have with this pump is when I add air. It takes several pumps to get the valve to release to allow the air to go in. If I release some air before pumping, it allows the air to go in and up to pressure without issue. Only my rear tire does this, so it appears to be an issue of the presta valve, not the pump itself. This is a minor inconvenience.
It's normal for Presta valves to be a little sticky. Good practice to give them a little push in before filling.
The only way to OP will be able to resolve this is to get one of his gauges calibrated.