low mpg slight backfire

[stubwing]

hey I have just picked up a 2000 MAX and that has been sitting for some time I cleaned the carbs and and it runs great, but
it has few issues! 1 it has a slight popping (small back fire) when I let off the gas. 2 the mpg really sucks its about 92 miles then my res. light
comes on. This is my 2nd MAX and the old one gettbacs about 105 miles before the light comes on. And the old one has 148k on it. the new one is
under 10k.

 

[maleko89]

Did you completely disassemble the jet block in each float bowl? Check coasting enricheners? Check rubber boots for cracks/leaks too.

 

[naughtyG]

+1 on what Mark said.

Did you completely take the carbs apart or just shotgun'd them?

Also, for the popping, check all your exhaust connections - if air gets in it will cause popping.