Anyone have thoughts as to why when I disconnect the hose from my vacuum pump the pump/chug sound I hear momentarily driving, is gone?. If its the pump itself I dont see why the hose being off would help as the sound would continue, possibly a clog up?. Placed my thumb over the pump line to feel and the air is pumping but its not smooth, its in time with the "chug chug chug" sound I get when accelerating. Thought this was initially the wheel on the thing having a wiggle but based on the pulsing movement of air in the line, seems just an aged pump. I dont think passed an annoying sound its anything to flip about yet, but all insight is as usually welcomed. Thanks guys.
Oh and at idle this thump knock sounding deal isnt present. I first looked into lifters, heads, etc and the shop had no notice of such when gaskets had work etc. Was going to video it but its so inconsistent that no desire, as well its friggen cold and I am avoiding removing the belt for a hand cranked test for a sound on it.