I am haven’t taken the unit apart yet. or looked to see if it your model or a different one. When I looked at the cap the air vent inside plastic cover is V shaped & sealed. I perforated the joint completely to allow for air & it gave more spray & better handle return but did not solve it completely. Shouldn’t the air vent be completely open & free for air flow? I am ready to cut the plastic off before I take it apart. What do you think?

Kate