MPG drop after Fuel Filter.

bordo380 · Jan 6, 2016

Hey guys. I'm new here with a new to me 2001 Excursion 4x4, my first diesel. I love this Forum. I've been learning a lot. Thank you.

So When I got this thing it was getting 16.6 hwy stock.

250K miles Added:
TS 6 position switch
S&B cold air.
From 305-70-16 tires to 285/75/16
4" procomp front lift
Ranch 9000's
Finally changed the fuel filter which was solid black. I did smell fuel before the change. It's gone now but my mileage has decreased.

I did pull a car on a trailer for 400 miles and i was very pleased. I got 10mpg going 70mph. What a beast. I love the 7.3.

I know this thing is a brick and may be just what it is.
Thanks in advance for your time.

6.0 Tech · Jan 6, 2016

How are you calculating you mileage? Towing will kill it, as will the fun factor behind the new chip. Once that wears off it will probably go up, unloaded at least.

superpsd · Jan 6, 2016

At 250K the injectors may need some attention in the near future. If you don't mind a louder engine get some single shot injectors and watch performance and fuel economy increase. Almost 17 highway is not bad for a heavy excursions at higher speeds. Nice rig!

bordo380 · Jan 7, 2016

Thank you! I also did the grill and lights.

Sorry I left off what I was getting afterwards. Hand calculating at 13.8 hwy running 70-75.

Is the 10mph decent for towing? I thought so but have no idea. I know my previous GMC 6.0 would have gotten a lot worse.

Yes the fun factor needs to wear off for sure. Also the chip messes up the mpg digital reading as it says I was getting 19.5.

rusty1161 · Jan 7, 2016

bordo380 said:
Thank you! I also did the grill and lights.

Sorry I left off what I was getting afterwards. Hand calculating at 13.8 hwy running 70-75.

Is the 10mph decent for towing? I thought so but have no idea. I know my previous GMC 6.0 would have gotten a lot worse.

Yes the fun factor needs to wear off for sure. Also the chip messes up the mpg digital reading as it says I was getting 19.5.

Your fuel quality and whether or not it is winterized affects MPG's, too.

Rusty

sootie · Jan 7, 2016

did you use OEM filters?

superpsd · Jan 7, 2016

One other thing to look at is cleaning or replacing the EBP sensor tube. They get clogged with soot. Invest in something to read the PIDs and DTCs. I use the Torque App Pro. It's 5 dollar for the app if you have an Android tablet or phone. I had to buy a 60$ Bluetooth adapter as the cheap adapters sometime will not talk to Ford's Protocol.

bordo380 · Jan 14, 2016

Thanks for the feed back. I had no idea about the EBP sensor and tube. I can't wait to see how bad it is.
I did use the OEM filter by motor craft but my cap is busted up. Maybe I'll get the whole assembly next time.

So single shot injectors are the way to go. I was hoping to make this thing more quiet. Ha.

I still need to add a 4" exhaust. Does this help much?

dsberman94 · Jan 14, 2016

Keep a muffler on it and it'll probably by decently quiet. Straight pipe is loud and you'll probably hate it towing.

superpsd · Jan 14, 2016

It will still be louder. The NVH from the engine itself will be louder without the pilot charge from the split shot. I run a 4" Banks monster muffler on my 7.3. You can see right thru the muffler with no louvers to cause turbulance and it is as quiet as a stock muffler.

bordo380 · Jan 19, 2016

Thanks fellas.

Also, how hot should these register? As you can see my temp gauge never gets over half way. I know this might be easier on the motor but maybe not hot enough to burn the fuel efficiently. I thought maybe my stat was stuck open....

This is after going 45 miles after fill up.

2001 Excursion 7.3L PSD 4x4 Limited
1998 BMW M3
1982 Jeep Scrambler
1964 VW bug sunroof 1641cc
2014 Jeep Grand Cherokee,Hemi, 4x4 Limited (wife's)

Arisley · Jan 20, 2016

That all looks fine.

bordo380 · Jan 21, 2016

Well I cleaned out the EBP sensor and tube last night. Hopefully this will help some. Is it smart to go ahead and replace the sensor?

2001 Excursion 7.3L PSD 4x4 Limited
1998 BMW M3
1982 Jeep Scrambler
1964 VW bug sunroof 1641cc
2014 Jeep Grand Cherokee,Hemi, 4x4 Limited (wife's)

mandkole · Jan 21, 2016

As long as the tube allows air through it, its fine. Is the EBP sensor not reading correctly? Unless you know its not reading correctly, I wouldn't replace it. Its not a commonly replaced sensor.

I suggest you invest in some data acquisition (AE, scan gauge, etc) to improve troubleshooting before replacing sensors.

bordo380 · Jan 23, 2016

Thanks for the feedback fellas. I need to go to my friends diesel shop and run some codes.

Ok new question. Is there an inline fuel flow meter to measure fuel consumption? I know they are out there but I'm not finding any and thought I would ask on here?

I filled up today and went on a 200 mile highway trip. The readout said 20mpg. I filled up immediately after and hand cal came out to 12.5. I think I didn't get it as full before but it's hard to tell. Ugh

Arisley · Jan 24, 2016

Fill up till you can see the fuel in the neck.

Any inline meter will measure flow, not consumption. Fuel is always flowing, there is a return line that returns unused fuel to the tank. Readouts are called lie-o-meters for a reason.

You will also get worse fuel mileage in the winter due to winter vs. summer fuel.

Do you have oversize tires on your truck, if so, is the speedo calibrated to mach. That will give you bad readings also. Along with oversize tires also hurting mileage.

cbf9703 · Jan 24, 2016

bordo380 said:
Sorry I left off what I was getting afterwards. Hand calculating at 13.8 hwy running 70-75.

Is the 10mph decent for towing? I thought so but have no idea. I know my previous GMC 6.0 would have gotten a lot worse.

I'm happy with 10-12 (uncorrected) towing depending on fuel, load, and terrain...

I usually run 35s on my ex and haven't recalibrated the speedo... I've been known to tow a loaded 25' toy hauler rolling 70-75 (uncorrected) on the interstate and never think twice. At this point I honestly go more on rpm than speed since it's off anyway. Interstates I usually just set the cruise rolling about 2k so I'm not completely killing my fuel mileage and rock on until I get to an area where I worry about cops.... LOL

I make a 450ish mile round trip pretty regularly and honestly it's a struggle for me to balance fuel mileage and the desire to just get there in decent time. If I'm good and keep it down around 1800 rpm on the interstate, it's a significant difference in how far the tank will last me.

dsberman94 said:
Keep a muffler on it and it'll probably by decently quiet. Straight pipe is loud and you'll probably hate it towing.

I have 4" with a muffler on my EX and no complaints, I can hear more tire noise from the coopers I'm running.

Arisley said:
You will also get worse fuel mileage in the winter due to winter vs. summer fuel.

Do you have oversize tires on your truck, if so, is the speedo calibrated to mach. That will give you bad readings also. Along with oversize tires also hurting mileage.

This.

I hand calculate and am usually 14.1-14.5 uncorrected for tire size unloaded and mixed use, but I'm not the most conservative driver either.

Sent from my XT1254 using Tapatalk

bordo380 · Jan 24, 2016

Thanks always fellas for the input. I'm a typical engineer and hate when things don't calculate.

I think I'm good on the tires 285/75/16. I used and GPS and at 70mpg my speedo is dead on. I've been going 70-80 on these highways where the speed limit is 75. 80 seems to be the norm. Of course this rig loves it.

I think I'm having an issue with the fill tube. I'm embarrassed to say but I ran out of fuel in this thing when I got it. The first time in my life. The light was on and said I had 40 miles to empty. I drove through 3 stations looking for diesel and it croaked just as I got over an over pass. So I never let it get below a 1/4.

Thank for the exhaust input. I'm going to look into a diamond eye with muffler.

I think I'm getting better mileage than I think. I found my favorite diesel station where the pavement slants away from the pump. I think I'll get a good reading there and the fill tube air bubble won't mess with me.

I did order the ELM327 to try and get some OBD2 readings. I'll report back.
As always thanks for the feedback.

IHPowerstroke7.3 · Jan 25, 2016

Don't drive at 75-80 mph and expect to get awesome fuel mileage. I don't know how your tires calculate in size but my guess the engine is in the 2200-2400rpm range at that speed. Keeping it below 1800-2000 rpm will get you way better fuel mileage/ range.

bordo380 · Jan 26, 2016

IHPowerstroke7.3 said:
Don't drive at 75-80 mph and expect to get awesome fuel mileage. I don't know how your tires calculate in size but my guess the engine is in the 2200-2400rpm range at that speed. Keeping it below 1800-2000 rpm will get you way better fuel mileage/ range.

That's a fact. One day it would be nice to invest in a gear vender gear splitter. I just haven't heard enough about anyone having one.

Tires come out to 32.8x11.22