What Is WRONG?????

[TORQUE THIS]

With almost 10,000 miles on my truck I am still getting 12-13 MPG. Has been this way since I picked it up in April. I have an Amsoil air filter and no muffler, other than that the truck is still stock. I drive the highway to and from work, very little city driving. However, while towing my boat to Lake George Labor Day weekend I got 16 MPG.



I am sometimes hard on the go-pedal from traffic lights. Usually drive 65 on the highway.



I have an automatic with 4. 10 gears. 2 WD.

 

[KatDiesel]

Well do you have gauges? If so do you spend alot of time with built up boost? The more boost you run at the more fuel you are using.



Have you considered a reflash of anysort? It certanly shouldn't hurt ya any.



I get about 14mpg and I drive hard and fast stoplight to stoplight, several people can atest to that.

 

[TORQUE THIS]

Kat, I have boost, egt, and transmission temp gauges. Highway driving at 65 I am running at 5 to 600 egt and 7 to 10 lbs of boost. I can get 21 lbs if I really step on it, egt's have never gone over 1000!



I keep hearing it will get better with more miles, I am wondering how true it is.



I really want to add an EZ and 275 injectors. Can't see doing it if MPG's keep up the way they are.

 

[HEMI®Dart]

From Fritzs' web page:



Poor Fuel economy:



Bad IAT (Intake Air Temp) sensor.

Bad MAP sensor.

Low boost due to leak or wastegate problem.

Weak or dead lift pump

 

[TORQUE THIS]

Looks like a trip to the dealer is in my future

 

[work2muchplay2little]

I ran mine completely stock until about 25, 000, only towed heavy once for about 1200 miles. Mileage kept creeping up until I was over 20,000, starting at about 14-15 and settling about 20 mpg. Personally, if it's running good, I'd give it more time, takes a long time to break one in and achieve final fit of all the internal moving components. You don't have synthetic motor oil in it yet do you?

 

[NVR FNSH]

What RPM are you at when running 65mph? My guess is ~2200rpm with 4. 10s and stock tires. Slow it down to ~1900rpm and check your mileage. Mine improved from 14. 5 to 17.



Brian

 

[Big White Beast]

Mine too.....

I got 11. 5 from the showroom. Dropped to 10. 5 when I loaded her down. It stayed that way till 10K miles. No sign of change. Then I added the EZ and 4" exhaust and it went up to 12. 5 steady. I think the EZ was the biggest difference. I got the milage jump before I put the exhaust on.



So if your worried about the EZ ruining your milage I wouldn't. If anything it will remain unchanged and you get the benefit of all that extra power. WARNING: power is addictive!!



Garrett

 

[Chris N5CWM]

Yes that's strange..

My previous Ram, a 2001 3500 4x4, ETC/5spd with

3. 54's got 16. 5 average almost all the time. This

was calculated by dividing the miles driven on the

trip odometer into the gallons it took to fill up

the tank. That truck did not have the overhead

fuel computer. Truck had 25,000 on it last check.

I got 13 MPG round trip from Houston to Lake

Travis in Austin, TX, towing my boat (6,000 LBS).



My current Ram, a 2001. 5 2500 QC 4x4, same drive-

train and gears, gets 19. 5 average, and this one

does have the fuel computer in the overhead

console; it routinely shows my avearage MPG on the

highway, not towing, 21-23 MPG, and if I do the

math via gallons used/miles, I get 19. 5 MPG avg.

I averaged 12-13 MPG towing a 29' travel trailer

(8,400LBS) from Houston to Kerville and back.



Do you have the overhead trip/fuel computer? If

so, do you reset the average MPG when you fill

the tank? Check the owners' manual for more info.

Basically you have to press both buttons at the

same time to reset the data.



-Chris

 

[SLightfoot]

With that 4. 10 in the rear end, stop and go driving is going to eat your MPG alive, especially if you are hard on the go pedal between lights.



If you want to REALLY see what your fuel economy is, fill it up one Saturday or Sunday, and take it out for a 2 hour cruise and back... go visit someone in another city, and then calculate what you get.



And yes, if your boost pressure is hanging around 9-10 lbs, you are burning fuel heavy. Stop and go can be a killer with a heavy foot.



You need to do a proper benchmark with highway driving to see if you really have something wrong or not.



That mileage doesn't sound out of the question for heavy-footed stop and go driving though.



Shawn

 

[joesoot]

Ditto on that...

11,300 miles since the end of February. . the 1st month I was getting 16-17 mpg on a daily 24 mile freeway commute...

Did a 900 mile trip 3 months ago with 1200 lbs of copper in the bed... @ 70 mph I got 16MPG... @ 75 I got 15. 5MPG

Flash forward to today another 900 miles today 15. 5 MPG(california diesel) @ 80mph for the first 400 miles... 13. 7 mpg(diesel from the '76 truckstop in Mesquite) @ 80 for the final 500...

Guess I need to drive at more consitent speeds before I worry, my filling habits are very regular... no gauges yet...

 

[HEYBOSS]

About the same

Mine does about the same, don't forget you have the training wheels and 4. 10 I get around 13. 5-14 and I'm heavy on the foot.

I did get 16 once when I went real easy on it, very tough to do

My truck just turned 15k.

On the trip to Fl and back it did 10-11 doing 70mph loaded to almost a GCWR of 19,000 5er if I slowed down to 60-65 it did 11mph just installed 4" exhaust and don't know what it will do, I don't expect any gain, love the sound and even harder on the go pedal now This mileage sure beats 5. 5mpg that my 3/4 with 1/2 the torque and power chevy did, so I don't complain.

 

[High Voltage]

Let's see... ... . 17/18 city... ... . 20/24 highway,and that's driving her hard. 65/85 MPH

13,000 miles

And California Diesel ... ... $1. 61

 

[Vaughn MacKenzie]

High Boost on highway?

Torque This, so does your boost run a steady 7-10psi at only 65mph when you are cruising at a constant speed on level ground?? If your cruising boost is that high there is some tremendous drag on your rig!



I have a 2wd but it's a shortbed 2500. At 65 in 6th I am only running 3-4lbs boost. When I was towing a car on a flatbed my cruising boost was about 8-12psi and my mileage was around 17. 5mpg. At a steady 65mph I get 23-25mpg.



Are you coming to the BBQ thing at Massdiesel's shop on the 13th? If you come we could check for a couple things like intercooler clamps or the IAT to make shure things are up to snuff.



Vaughn

 

[pwr2tow]

Ditto no what HEMI DART said. Definatly check that IAT sensor, I was makeing 8. 5 MPG towing before I changed the IAT, now I get 10. 8 and that is towing everything in my signature, alot of weight. If I slow down from +70 to 64 MPH I can get even better numbers.

Ron

 

[jjohnson1177]

I agree with what Vaughn stated, 8-10 pounds of boost is way to much for crusing. If you're not towing somthings not releasing. I'd check brakes, ect.

 

[Mark_Kendrick]

My truck has 26 k on it now but... I get about 16mpg at 70-75 unloaded/hwy. If I slow down to 60-65 I get 18-19 unl/hwy. I've found that if I don't get in a hurry keep the revs below 2000 for the most part mileage is much better.

I recently pulled a 30ft goosneck loaded with a 50 hp johndeer, all the implements and some bundles of hardwood flooring(total of 18000lb). 60-65 got about 11-12 mpg. 75-80 on the turnpike got 8. 5 mpg.



I've been thinking of adding a box (ez probably) and mild propane. Anyone have info on effects to mileage, power, & reliability for the HO motor?



Thanks,

Mark

 

[DaveN]

Tow something heavy in a hilly area all day at highway speeds. That helped my MPG's by about 4 mpg.....

 

[TORQUE THIS]

I double checked my boost gauge this morning. At 65 on level gound with cruise on, 8psi boost and 700 egt's, 2200 RPM.



At 55 with cruise on, again level ground, 5 psi boost and 500 egt's, 2000 RPM.





Should I order another sensor from the dealer, how much and is it easy to remove and install??





Thanks for all the replies

 

[Todd T]

I think the fact that your boost was higher should tell you, you were either not on level ground or headed into a head wind.



8PSI to stay going 65MPH is not level ground or ?.



do a search on "Cleaned AIT Sensor" and Marco gave readings for it in there.



its easy to remove, just pull it, and replace, or clean it with some electric contact cleaner.



what are your RPM's at that speed? just to help me relate.