Getting 14.5 mpg. Good or bad?

[PAExplorerXLT]

I have measured my mileage three times now and it is consistently giving me 14.5 mpg in around town driving. Considering that my CEL is on indicating an O2 sensor issue, is this about what you are getting?

 

[AP9]

That's not bad. With the OHV V6 and 4WD I typically get about 15 or slightly higher in the summer, but it drops to 12-13 in winter.

 

[SoNic67]

That's what I have around town too (V8 5.0L). Maybe 15mpg... Every time you break at a stoplight, you lose a bunch of energy, because of the sheer vehicle mass and speed. Energy costs gas to make and you will dissipate it as heat every time you stop.

On the other hand, on a head-on collision with a economical mini-car, that huge kinetic energy will help you survive. Consider it a life insurance.

 

[drdoom]

Not too good, (20 mpg here) but the sensor replacement will help, and pays for itself.

 

[J_C]

Too many variables to consider. Around town, some will drive long enough to get the engine up to temperature for a large % of the trip so their ECM operates in closed loop mode for higher efficiency and MPG, and some won't.

Having a bad O2 sensor means you never reach that higher efficiency. No point in considering MPG till all sensors work, no trouble codes remain.

 

[koda2000]

the CEL being on means an emissions related sensor is not communicating correct information to the PCM. w/o accurate data, the PCM can't adjust air/fuel ratio for optimal performance and economy. in addition, as J C said, there are too many variables. my V8's typically get around 16-17 MPG around town and 22-23 MPG highway, but I live in a rural area with little traffic and my highway drives are on relatively flat roads, again with little traffic. during the summer, running the A/C constantly and the engine breathing very hot air, 14's around town were possible.

 

[ThreeJs]

right now mpg is a consistent 15.5-6 per gal. In town driving, A/C on, mixed 35-55 mph driving, running regular 87 unleaded. 96 4.0 OHV, Auto, 4x4, stock size 16" tires.

 

[1996BLKBauer]

That seems pretty good to me, I on average most city driving get 13.8-14.5 with my V8 AWD Eddie, so I would say you are doing pretty good.

 

[bobflood]

To paraphrase an old military saying" " Discussing mileage amongst Explorers is like discussing virture amongst ******."

 

[4rd Xplora]

17.8 on the average. Total of 40 miles round trip to work and back M-F, about 36 of which is highway at 75-85 mph and some light weekend work. Not bad for an 18 year old mostly original "Buddy L" toy truck. (Most of the older guys will know what "Buddy L" is )

 

[drdoom]

Good one, Bob!

 

[PAExplorerXLT]

I just figured 15.2 mpg in city driving. There are 40mph stretches but for may be 5 5minutes. The rest is stop and go. I have 0171 and 0174 codes on and have given up on them. Interestingly, my mileage now is better than the 14.5 I reported when I started this thread. Someone said lean error codes actually cause more fuel to be used.

 

[Sedition]

550 kilometers to a full tank of regular unleaded gasoline while hauling a full load of tools with a lead foot.

 

[SoNic67]

I average 14.5-15.5 mpg mixed driving - Highway and town (with heavy traffic at times), usually 13 miles each trip.
If you drive shorter trips, mileage will suffer, especially in the winter.

 

[chefduane]

Wow, I must be doing something right. My Ultragauge (Ultragage?) indicates 18.6mpg avg for in-town and highway. I live about 20 miles from where I work and it's about half and half highway/town. I have done a MAF clean, new IAC, new coil pack/plugs/wires, PCV, and EGR, so she breathes a little better.

 

[koda2000]

Wow, I must be doing something right. My Ultragauge (Ultragage?) indicates 18.6mpg avg for in-town and highway. I live about 20 miles from where I work and it's about half and half highway/town. I have done a MAF clean, new IAC, new coil pack/plugs/wires, PCV, and EGR, so she breathes a little better.

That's pretty good, but keep in mind the OP's CEL is on. Depending on what the issue is, this can have a huge effect on fuel economy. The CEL indicates some sort of emissions related problem, almost all of which will effect mpg in a negative way. To my way of thinking, there's no point in even checking fuel economy with a CEL on.

 

[chefduane]

Well, I also recently added a Bluetooth hands free phone microphone. I wired a connection directly to the PCM and when I'm driving I whisper in to the mic: "you are a wonderful automobile, you are strong and powerful. You have sleek lines and other cars envy you.." Seems to work.

 

[bluestream1]

You cant get out of open loop ecm with a check engine light O2 sensor issue. When the engine is first started the system goes into open loop operation. In open loop, the ECM calculates the Air/Fuel ratio based on inputs from the coolant and MAF sensors. The system remains in open-loop until the following three conditions are met:

Coolant temperature above 105°F.
Oxygen sensor has varying output voltage (indicating it is hot enough to operate properly).
A specific amount of time (preprogrammed into the MEM-CAL) has elapsed.

 

[koda2000]

When I first bought my 2000 AWD Mountaineer, it had a bad thermostat (stuck open) and that caused the truck to run in open loop mode all the time. The MPG sucked 13-14 Hwy. It finally throw a code (P0125 - failure to enter closed loop mode). I replaced the thermostat and the mileage returned to a more normal (normal for me) 17'ish in town and 22 Hwy. Driving in open loop mode is like driving with the choke on. Bad upstream O2 sensors can cause the same condition.