Like Sun used to say, "We test, not guess". One of their tuneup machines had a fuel pump tester- - - -better known as a pressure/vacuum gauge. I've stopped wasting my time trying to tell people how to test a fuel pump. There are a lot of "wheelbarrow mechanics" on Stovebolt- - - -roll a wheelbarrow full of parts up to the truck and start swapping things out- - - -hoping the problem will magically disappear!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!