Is it standard procedure to disable the fuel pump prior to testing to insure the Dry compression test is in fact "dry"? I've heard this from a few sources, but I forgot to do it. So does that make my results wet, dry, or neither. I know oil seals better, but my results were high and +- 2 psi between cylinders, so I've never bothered w/ the oil.

 

well you should disable the fuel pump just for the purpose it isnt spraying during the test and washing down the rings...this will cause them to start using oil as the gas washes the oil off...simply because it isnt being burnt...

when I do a compression test I unhook the coil power....pull the fuel pump fuse...pull all spark plugs (all of them) and zip tie the throttle wide open...crank the engine so it make 3 full revolutions on each cylinder to keep all readings even...

 

Why zip tie throttle open when fuel pump is already disabled? So my test w/o fuel pump disabled of 178-182 psi between cylinders was not really dry, but not really a legitimate wet test either. Compression tests are kinda like Prostate Exams. They should be really be done every so often, but nobody shows up early for the appointment. One of my back plugs was slightly cross threaded many years ago & I keep thinking I'm going to see the plug bouncing down the highway in my rear view mirror, every time after plug changes. And I did alot of regapping until I finally settled on Side Gap. Thought about using a thread chaser but the threads are tapered aren't they?