so my MPG's went down to 13-14 from 17-18..... i have a new overflow valve, clean air filter, i only let it idle long enough to cool down the turbo. my driving habits havnt changed. any ideas??

 

When did you change the fuel filter last?

 

As Blue said, fuel filter and pre-filter can change your mileage drastically........ Mine jumped almost 4 MPG after a bout with a blocked pre-filter.

If that doesn't do it, time to get a fuel pressure gauge on there and test the LP.

 

i cant believe i overlooked that.... it was changed probably 9 months ago or so when my wife moved our stuff down here, it had cracked on the interstate and she limped it to a shop who replaced it. i will try to get a new one on there tonight. i know it has been posted before so can someone point me to the instructions on how to clean the pre filter? thanks

 

Prefilter cleaning> http://dodgeram.org/tech/dsl/filter/pre-filt_clean.htm

Fuel pressure gauge> http://www.cumminsforum.com/forum/94...-12-valve.html

 

thanks infidel

 

so i cleaned and changed that...... i found it much easier to remove the two nuts holding the brake fluid resivoir on and set it down a little farther on the inner fender...... it gives you much more room to get at the filter/pre filter. i also didnt spill a drop of fuel when changing the filter.

 

Is the truck blowing more smoke? You could check to see if you have a boost leak. If you are leaking air out one of the intercooler boots that will cause the truck to burn a lot richer. How fast did your milage go down hill? Are we talking over night or over a month or two?

 

I have a fuel pressure gauge and I see 24+ psi. All the mods in my sig and mileage is still 11/16. abysmal.
Just installed a 215 pump hoping that was the culprit. Nada.
driving me crazy.