I have really bad fuel mileage on my 2001 Cummings diesel.
Ive added and edge ez mod. and a ats propane injection system. All that just put me up to 17 mpg. I do have a code of P1693. The truck runs fine but I dont know where to start/ HELP

 

1693 is a companion code which means there is another code in there but you'll have to have a CAN scanner to see it...IIRC. Not all scanners will read Dodge specific codes.

 

I have an 01 with the manual trans. Best MPG's I get is around 18.x, so I'm not sure you have a problem.

 

with propane, you should get over 20 depending on your foot

 

It is spelled CUMMINS not cummings. But you should be getting better mpg than that.

 

please pardon the spelling. I should have proof read it after the spell checker got to it. However before i added the propane injection and the edge mod. I was only getting 11-13 mpg

 

Do you have 4.10's?

 

My 2001 has never got the mileage everyone else claims. I remember reading years ago that there was a sensor that might be causing this anomaly. It works within spec, but some do not read properly and might cause bad mileage. I ave. 14 in town and 17 on the highway. auto with the taller 350 gears. stock tires.

 

I do not have 410s i have 350 gears according to the tag in the glove box

 

350's

 

what sensor is that, cuz on my 02 (with 3.55 gears) im lucky if i get 16... im norm looking at 14.5-15...

i dont have any codes, my truck is stock (no computer mods)

 

Actually there is 2 sensors that you can take out and clean. 1 is the MAP (pressure sensor) and the other is the IAT sensor. The MAP is located on the block behind the fuel canister and I can't remember where the other one is...use the search function and you'll be able to find it.

 

You haven't said how you drive the truck,horspower required what speed you generally drive, or whether you frequently tow. Also, do you start it up and let it idle until warm?

High speed driving is a major cause of low mileage since the horspower requirement goes up with the square of the speed increase.

 

I've drove a full week going 55 another, 65,75,... still the same 15.5...same fuel station, same pump...

 

I drive aprox. 50 miles per day mostly interstate. high speed of 70-75, I live on a mountain , mostly non towing. I leave the block heater pluggged up during winter months and start it aprox 15 - 20 min before leaving for work.