How to improve MPG in 2006 Jeep CRD?

[justinmc]

I bought it used 3 months ago and I've been getting 17-18 US MPG with a 50/50 mix of highway/city driving. I'm not doing hard acceleration and I'm coasting to stop signs, etc. This is calculated by hand MPG not EVIC.

I'm actually getting less MPG because my spedometer is off by about 10% so it shows 80km when it's actually close to 70km. So that works out to closer to 15-16 US MPG. It seems I should be getting closer to 20-22 US MPG at least after reading various discussions about it.

The air filter is new, fuel filter and oil changed within the last year.

Thanks,

Justin.

 

[KJ604]

welcome to owning a KJ.

mine does the same thing. lots of people say 20 MPG but ive never seen anything like that so im not sure. i get in the 16 US MPG range. and i do my own mileage calculation. and you have to live with it.

now youre going to get a bunch of peope telling you you shouldnt have bought a jeep if you care about mpg.

and youre going to get people telling you to change plugs and all that.

ive done plugs and coil packs since i bought my jeep a year ago. ive run some premium fuel through it. ive run injector cleaner through it. new air intake filter. mileage has stayed the same.

 

[tommudd]

welcome to owning a KJ.

mine does the same thing. lots of people say 20 MPG but ive never seen anything like that so im not sure. i get in the 16 US MPG range. and i do my own mileage calculation. and you have to live with it.

now youre going to get a bunch of peope telling you you shouldnt have bought a jeep if you care about mpg.

and youre going to get people telling you to change plugs and all that.

ive done plugs and coil packs since i bought my jeep a year ago. ive run some premium fuel through it. ive run injector cleaner through it. new air intake filter. mileage has stayed the same.

He has a CRD

 

[tommudd]

I bought it used 3 months ago and I've been getting 17-18 US MPG with a 50/50 mix of highway/city driving. I'm not doing hard acceleration and I'm coasting to stop signs, etc. This is calculated by hand MPG not EVIC.

I'm actually getting less MPG because my spedometer is off by about 10% so it shows 80km when it's actually close to 70km. So that works out to closer to 15-16 US MPG. It seems I should be getting closer to 20-22 US MPG at least after reading various discussions about it.

The air filter is new, fuel filter and oil changed within the last year.

Thanks,

Justin.

Hello Justin
There are a few CRD owners on here
BUT I would suggest going over to LOSTJEEPs , thats where most of the Liberty CRD owners hang out at it seems, great site and a lot of knowledgeable people

 

[KJ604]

He has a CRD

glow plugs?

:gr_grin::gr_grin:

i did notice it was CRD but if everything's new and there are no CEL's or obvious reasons to be loosing MPG's then that probably just the way those motors are too. I guess i cant speak from experience since I have a gasser but the situations sound similar.

definitely seek the advice of the people in the CRD sections as well. I am only speaking from my experience.

 

[justinmc]

welcome to owning a KJ.

mine does the same thing. lots of people say 20 MPG but ive never seen anything like that so im not sure. i get in the 16 US MPG range. and i do my own mileage calculation. and you have to live with it.

now youre going to get a bunch of peope telling you you shouldnt have bought a jeep if you care about mpg.

and youre going to get people telling you to change plugs and all that.

ive done plugs and coil packs since i bought my jeep a year ago. ive run some premium fuel through it. ive run injector cleaner through it. new air intake filter. mileage has stayed the same.

Thanks for the welcome and quick response. It just seems like I'm missing out so I figured I'd ask. I cleaned my MAP sensor too and was thinking checking the intake elbow but that seems like a pain.

 

[justinmc]

Hello Justin
There are a few CRD owners on here
BUT I would suggest going over to LOSTJEEPs , thats where most of the Liberty CRD owners hang out at it seems, great site and a lot of knowledgeable people

I'm on lostjeeps too but I posted a message yesterday and hadn't had a reply so I figured I'd try here. I have had some good info from other posts I've made on lostjeeps so I'll check back there and see if I can get some help. Thanks.

 

[justinmc]

glow plugs?

:gr_grin::gr_grin:

i did notice it was CRD but if everything's new and there are no CEL's or obvious reasons to be loosing MPG's then that probably just the way those motors are too. I guess i cant speak from experience since I have a gasser but the situations sound similar.

definitely seek the advice of the people in the CRD sections as well. I am only speaking from my experience.

I thought you were talking about glow plugs. No CEL, as suggested I'm going to try back on Lostjeeps because I think I should be getting better MPG than a gasser.

 

[turblediesel]

Best I ever got was 25 mpg... once. When new I got 23 mpg summertime and 19 mpg wintertime. Then it got the F37 reflash from the (damn) dealer and thereafter only got 19 mpg summer, and 14 mpg winter.

Green Diesel Engineering can reflash your computer and you might get better mileage.

 

[justinmc]

Best I ever got was 25 mpg... once. When new I got 23 mpg summertime and 19 mpg wintertime. Then it got the F37 reflash from the (damn) dealer and thereafter only got 19 mpg summer, and 14 mpg winter.

Green Diesel Engineering can reflash your computer and you might get better mileage.

So you didn't get the F37 removed? I think mine is F37 since it 1900-2000 rpm at 100km/hr and it should be 1700-1800 after it shifts. I looked at GDE but it's more than I want to spend so I have a cable coming to read/write my ECU and I'll check out the bin and perhaps modify it but the TCM for the F37 is another issue. Thanks.

 

[turblediesel]

My CRD is hibernating patiently until I get ahead on firewood and other projects. I've got the GDE tune but haven't fired it up yet. Lost in the timing belt, stud replacing, input cleaning, provent, weeks kits, and glow plug swapping project.

You're a better man than I am for chasing down the programming path. Lots of good info and debate on the different ways to change the CRDs mind. I went with GDE because computers and I don't get along.

Elbow cleaning only helps so much; The intake passages in the cam carrier need cleaning too. All those restrictions can affect performance and economy.

 

[justinmc]

My CRD is hibernating patiently until I get ahead on firewood and other projects. I've got the GDE tune but haven't fired it up yet. Lost in the timing belt, stud replacing, input cleaning, provent, weeks kits, and glow plug swapping project.

You're a better man than I am for chasing down the programming path. Lots of good info and debate on the different ways to change the CRDs mind. I went with GDE because computers and I don't get along.

Elbow cleaning only helps so much; The intake passages in the cam carrier need cleaning too. All those restrictions can affect performance and economy.

Sounds like you've got your hands full for sure. I have an electronics and IT background so I do okay with computers.

 

[turblediesel]

Show me to your UNIVAC CP-818 and I'll show you how to "TILT" the registers upside-down.

Since then computers have only become more complex and worthless. Isn't technology almost great?

My CRD comes to mind occasionally. I'm realizing it's the biggest space-sucker in my small shop. All the loose parts, the bench full of new parts, and the dusty lump in the middle. I'll be working on it soon just to get it out of there.

Good luck with your CRD. I do recommend doing everything at once in the engine bay in spite of my non-progress. It's a lot of work and expense but it should be good for some miles before it smacks a moose.

Looking at an '89 Dodge shortbed 4x4 with no rust for transportation... for less money than the CRD mods.

 

[justinmc]

Show me to your UNIVAC CP-818 and I'll show you how to "TILT" the registers upside-down.

Since then computers have only become more complex and worthless. Isn't technology almost great?

My CRD comes to mind occasionally. I'm realizing it's the biggest space-sucker in my small shop. All the loose parts, the bench full of new parts, and the dusty lump in the middle. I'll be working on it soon just to get it out of there.

Good luck with your CRD. I do recommend doing everything at once in the engine bay in spite of my non-progress. It's a lot of work and expense but it should be good for some miles before it smacks a moose.

Looking at an '89 Dodge shortbed 4x4 with no rust for transportation... for less money than the CRD mods.

Unfortunately I don't have a Univac, but I do own several 8" drive based computers including an old Wang and an NEC. My 1970s DEC Writer printer is going to be on the new NBC series "Timeless" when they do a moon launch episode.

The complexity of the CRD is a bit mind boggling so I understand completely what you're saying. I still find computers and most electronics simple though.

Thanks.