My Ram has a hemi and was gettin sweet mileage when i bought it(15.4) now with 59K on it it is gettin worse. I do have a CAI Exhaust TB Spacer MSD wires NGK copper plugsand JET module. When i run premium gas i get 12.8mpg and on reg or mid 13.5. Im gonna start by takin that god dam JET out cuz i think that sux! Any Ideas???

 

My manual says not to use premium, as it offers no benefit. The HEMI doesnt need it, so its just a waste of money. Also, most gas in the US now has methanol in it, which was not in there back when you bought your truck. It reduces pollutants, but decreases mileage. You also might have developed different driving habits over the years.

 

Remove Jet & TB spacer. Clean TB when you remove the spacer. A dirty TB (and the Hemi TB gets VERY dirty in a relatively short period of time) is often the culprit of poor gas mileage and will lead to rough idling, stalling, etc. if left uncleaned for long periods...

 

10% ethanol is the problem. Its the great American scam. Kills mileage and makes the oil companies richer, raises food prices and does nothing for the environment due to the oil used to make it!!!!!!!!!!

 

What they said. Forget the premium gas (don't know why people fall for that), and ditch the TBS (you do need a paperweight, right?). Clean the TB. I'll bet you see serious improvement. If you could get your money back on the paperweight, that'll probably buy a tank of gas.

 

Not to be picky, but it's methanol (with an M) they add to gas, not ethanol (such as E85, made from corn). They are different things, but your point is right, it does reduce efficiency. Ethanol and ethanol blends require a specially modified engine.

 

Not to be picky but it is ethanol with an E like E-85 and most places E-10 meaning 10% Ethanol. Methanol is the stuff that is poison to cars/trucks and wrecks fuel systems.

 

actually, it is ethanol that's mixed in gasoline, and it is made from corn. can also be made from sugar and a bunch of other stuff. and it DOES NOT reduce pollutants. it simply shortens the emission re-cycle time. however, methanol is sometimes used for biodiesel.

 

Because of its poisonous properties, methanol is frequently used as a denaturant additive for ethanol manufactured for industrial uses— this addition of a poison economically exempts industrial ethanol from the rather significant 'liquor' taxes that would otherwise be levied as it is the essence of all potable alcoholic beverages.

 

Thanks. Now I wanna replace the JET with a superchips flashpaq, would you recommend using premium then, like superchips says to.