I opted for the cheaper standard motor products MAP sensor but the Mopar one seems readily available online. I kept my old MAP sensor for backup in my glovebox but ever since I changed it along with the o2 the truck starts up better/smoother and idles/drives a bit better. I never personally tested the voltage rating on my old sensor but I'm assuming it was original and worn out due to the fuel vapors/carbon over time....quite a few sensors were I'm guessing by their looks. Now that I cleaned out my IAC and throttle body I want to start calculating my mpg to see how it improves. A bad batch of gas had me at only about 8 or 10mpg at best last winter. I have fresh tuneup parts, new o2 and map and clean iac and TB, new fuel pump now alongside with K&N CAI and dual exhaust, although those weren't the night and day difference that would magically make the truck get 20+ mpg like some people over the years in online forums would claim lol.

unfortunately I'm on OBD1 in my ram so I don't think there's anything readily and easily available to monitor stuff to see where I could improve stuff too like you can on OBD2 vehicles with a bluetooth plugin and cheap app and phone

I'm eager to see if a new MAP sensor, either Mopar, (or I can vouch standard motor products seems to be decent) improves your mpg any

 

 

I think I found the issue in your original post:

Big, heavy, large displacement V8 engine, four wheel drive, with large tires. That combination has never been miserly with fuel consumption. The difference when it comes to your truck versus those of the 80s and 70s is the amount of pollution it spews (less) and the amount of power it produces (more) at the same rate of fuel consumption. What make you think it should get better fuel economy? You also need to factor where you're driving -- city vs highway; flat vs hilly terrain; etc.

My old '97 5.2L 2WD would get 17mpg provided I was on very flat terrain for distances of hundreds of miles; otherwise, it averaged 15mpg for a 35-mile (mostly highway) commute. Its main advantage is it could haul much more than my Mazda 3. Your truck's advantages are the ability to haul heavy loads and also traverse off-road terrain. There is a lot of give and take when it comes to truck ownership -- well, that is until Tesla and others start producing pickup that aren't powered with fossil fuels.

 

I've got a gen3 2500 ram , 5.7 hemi . Not an expert , but I have learned my way around the torque pro app . Not the easiest thing to do though , and I'm sure it's not as good as more expensive scanners . But for 20 American , it's worth the time to learn to use it .

Ive used it to check and reset trouble light , monitor oxygen sensors , and monitor fuel trim data . That's what you want.....fuel trim data . If your unfamiliar with that term , Google it and earn .I can answer specific questions , but to try to explain the whole deal would be pointless . You gonna have to play with it yourself. And don't listen to anyone who tells you fuel trims should be zero...haha . The app does way more than what I mentioned though .

 

My ex had a 2000 Grand Cherokee with a factory installed MPG monitor. Watching the instantaneous MPG did not make sense a lot of the time as in driving a constant 30 MPH on a flat road and seeing 17MPG and then driving 65 and seeing exactly the same. I can't help but think that there was a lack of factory engineering to make it do better. I drive with an intent to be economical most of the time and my commute is a 55 mile round trip. I do everything I know to get the best economy and it doesn't seem to matter what I do as the result is always around 15MPG. On the plus side, my brakes, my tires, and the stresses on my drive train are less -- something is not going to wear out as soon as it would otherwise. I wish Elon Musk would just manufacture a stripped down low tech commuter car. I'm seriously watching the EV conversion crowd and have two little Geo Trackers that would be perfect and a ton of fun.

 

From what I can ascertain in the original post, I'm with Gary L, in that it's probably normal for your truck as is. The 5.9 was the baby "entry" level engine for the HDs so it works hard in that truck. Also, you haven't mentioned doing a tune-up, changing filters, oil viscosity, thermostat, deathflash, air temp, tire pressure, brake condition, alignment, or what's in the bed. Changing one MAP sensor is not going to be the whole answer here.

 

I'm thinking normal would be variable mpg with respect to towing, city vs hwy, etc. Its getting a very consistent 11 MPG - and that tells me there is a factor in the mix that outweighs all others. Its not that I'm focused on number 11. I'm focused on its freaky consistency, when the use pattern is not consistent. One tank was mostly city, another way highway, one was city and towing city. I want to discover what that non-use factor is, and if I can make it less of a factor, I am asserting I will see my MPG become variable with use.

PO replaced the wires, cap, and plugs - not more than 5k miles on those. It has fresh factory spec weight dyno oil in it. Starts easily, never stalls, runs pretty good. The wheels are 2014 factory alloys, and I'm running LT tires that you see on 1500 trucks. Brakes are all fresh and working flawlessly (but the abs isn't operational). There was no factory tag on the computer, tire pressure is 38lbs. Fresh alignment, new front suspension, ujoints all good, and the bed is normally empty.

I haven't touched the throttle body, all I did was replace the o2 sensors. I did get rid of the junk CAI and grabbed the factory setup and put it on before we started driving it. The truck was running super clean when it went in for its snif test, which is done at load and idle.

No codes are being thrown.

Next steps, pull the TB and clean it and the sensors... when it gets a little warmer - not into working on things when its below freezing outside...

 

You telling me you don't like to freeze holding cold tools!?!?... I'm right there with you lol