Getting Worse Gas Mileage Now

[mattroxhere]

I have an 85 GMC with a crate 350 and crate 350 turbo trans. It has an Edlebrock 680 carb, 3.42 gears and 3/4 ton running gears. I use to get 9-10 mpg now all of a sudden I'm getting 4-5mpg. What happened or what can i do to get better gas mileage or at least back to what i was getting? Thanks for reading, any help would be much appreciated, its a daily driver.

Thanks,
Matt

[Boone83K10]

Lift up your right foot.

 

[Captkaos]

What changed?

[dvdswan]

when was the last time you did a tune up?  do you still have all the emission junk on the engine?  did you fill up at an unknown gas station or is this over several fillups?

[mattroxhere]

I thought it might be my timing and plugs but that didn't help now its flooding out randomly and i got gas sitting in my carb.

[bake74]

I thought it might be my timing and plugs but that didn't help now its flooding out randomly and i got gas sitting in my carb.

     You might have got some bad gas, sounds like you need to tune up your carb.

[mattroxhere]

Ya I'm probably gonna get it rebuild thanks for the help guys.