So we've been running the 2000 Ram 2500 for a couple months. About 185k miles, automatic, 4x4, with 4.10s. It has 20" wheels with 275 60s. I replaced both o2 sensors prior to putting it on the road. I've corrected for the tires, and its getting a VERY consistent 11 MPG - pretty much doesn't matter who is driving or where we take it. Even has some trips include pulling the car trailer empty. I'm thinking the mpg should be more variable than that - therefore something isn't right, so I'm curious about what is the root cause.

I have a Bluetooth obd2 reader and the torque app. I'm thinking I should be able to just plug in and monitor some sensor and get an idea of what is not quite right.... Typically, I'd start with injector cleaner, progress to the ignition system, clean the sensors and TB... But, why not try to use new technology to see if its possible to get to root cause quickly. Plus, its cold and maybe I'm being lazy... Oh, and I already ran the fuel injector when I first put it on the road - just because it had been sitting for so long...

So anyone master the torque app with these magnum v8s? I'd like some pointers...

 

something that can possibly increase the MPG is replacing the MAP sensor even if it's not reading bad, over time I've read the fumes/exhaust end up hardening the diaphragm and it doesn't read the same

there was a huge big topic here I found via google circa 2009 or so discussing it too but I didn't bookmark it and for the life of me can't find it again, might have been in the Dakota forum.

anyway, another topic talking about it too https://bobistheoilguy.com/forums/ub...pics/1487934/1

 

Ugh... If he only JUST replaced the MAP sensor it would be a smoking gun. Should only make one change at a time! Plus tuneups tend to have similar effects if they are needed.

But a quick search on that took me to a page that had a table showing pressure to voltage output.
https://troubleshootmyvehicle.com/ch...e-map-sensor-2

I have looked at the vacuum signal in torque.. now wondering if the MAP sensor is the source for that value display in Torque.
Thanks for that tip, I think I'll chase that lead.

 

Is this 11mpg as indicated by the bluetooth app or an actual 11mpg as determined via the gas pump, your odometer and a calculator? I have a bluetooth OBDII gizmo and am using the OBD Fusion app. The MPG function on my app is totally out to lunch. I looked into this a little and have decided that there just isn't enough data from the available monitors to do a decent job of monitoring fuel economy. My 97 1500 5.2 2wd is getting 14.2 to 15.5 mpg measured fuel economy and I drive mostly like a geezer wearing a hat to church.

 

Calculated from adjusted miles(reads 10% under) from last fill divided by number of gallons to full. We have 4 drivers, all different styles and paths traversed... yet the mileage is ALWAYS the same. Seems statistically unlikely.

 

I had an old chevy blazer that was like that. It didn't matter what I was doing.... 11 mpg. Didn't seem to matter how many folks were in it, how much gear in the back, or what I was towing.

 

With its 8800lb rating and factory lift... its a beast of a truck.... but I still think it should do a little better when it comes to mpg. I may take a look at the MAP sensor if it warms up over the long weekend.... unfortunately I have other surprises to deal with... like the axle fail on my car trailer... I've grown to really hate the rust belt.

 

Like duct tape and that'll be fine! What engine does your 2500 have?

 

5.9 Magnum V8... guess I forgot to include that important fact !

 

If I had to guess I would say MAP sensor my man