recently i had a tune-up on my 76 scout and was told there were no compression leaks and it was a strong motor. On my way to work the other day i started getting a lot of backfire and the engine started to sputter and tried to cut off whenever i tried to accellerate(going uphill was especially bad). Even though i had to baby it to reach 40 mph it would only sputter when i tried to go faster. ANY HELP/SUGGESTIONS WOULD BE MUCH APPRECIATED!!