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Discussion Starter #1
Previously, I've stated that I wasn't completely happy with my fuel mileage. To date, my best mileage has been 25 MPG highway. I believe part of that is due to the speed limits in this part of TX being mostly 75 & 80 MPH. I now have about 4700 miles on my Lariat Long Horn 4X2 and my MPG has suddenly dropped. I was getting a solid 22-23 MPG for daily commuting. Now, my MPG is down to 18-19 MPG for the same drive. What could be causing this? Nothing is changed, no towing, no EVIC warnings, nothing. I've got that gut feeling I have a lemon with a nice helping of douche nozzle customer service. The selling dealer wont return my calls or even book a service appointment to look into it. Have I made a $50,000 mistake by going with this Ecodiesel vs. the reliable and proven VW/Audi diesel I was originally looking at? ****, I think I've heard of less issues with the Chevy Cruze diesel!
 

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Strange. You have to figure that there is a problem if you really haven't changed much at all. I'm sure the dealer will get back to you. Don't throw in the towel just yet.
 

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I am surprised by all the people mentioning bad dealers. I have 4 within about 45 miles of me and if one was bad I would drive to the next. Maybe others are in more remote parts of the country but I would call Chrysler customer service to report them and get them involved if thats the case
 

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Bad fuel? I could be completely wrong. ..just a guess. I know personally, my mileage on all of my vehicles drop in the winter months due to warming up the vehicle. Texas folks may not be as likely to see that. I know I see a 3-4 mpg drop when it's cold. ( on my old truck).
 

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Discussion Starter #5
Bad fuel? I could be completely wrong. ..just a guess. I know personally, my mileage on all of my vehicles drop in the winter months due to warming up the vehicle. Texas folks may not be as likely to see that. I know I see a 3-4 mpg drop when it's cold. ( on my old truck).


Well, I thought I might have a fuel problem, so I went to another station and filled up there & there was no difference whatsoever. I'm not aware of anything called "winter diesel" in this part of the country. I use the remote start on cooler mornings, but usually I don't let the truck idle more than 5 minutes. I added a considerable amount of air to my tires Saturday, so I will see if that makes any difference at all this week...
 

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Are you judging this by the EVIC? I found on my last tank that is was under evaluating by about 4MPG. I was starting to wonder as at the end of the tank it showed about 21MPG and I had some Hwy miles on it but a manual check showed almost 25MPG.
 

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Discussion Starter #7
Are you judging this by the EVIC? I found on my last tank that is was under evaluating by about 4MPG. I was starting to wonder as at the end of the tank it showed about 21MPG and I had some Hwy miles on it but a manual check showed almost 25MPG.

Good point - I look at the EVIC instant reading and then the average. Both are very close to each other. Maybe I should just turn that off for a while & do a manual calculation per tank & see if its different.


This does raise another question. Why would the EVIC suddenly start reading erroneously? Are they prone to that?
 

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Hershey,
When I bought my truck in Aug, I was getting about 27-28 MPG (US Gallon, all highway driving). Since then my milage has been slowly dropping as well. I now have just passed the 10,000 KM mark and my EVIC is showing 18.2 MPG (I do hand calc on every fill-up, but I still have 1/4 tank of fuel left, so I dont know if the EVIC is reading inaccuratly). I have not modded the truck in any way. it still has that rediculus nose dive rake and nothing added for winter weight, no fuel additives except for the winterized diesel at the pump, if they have even started adding it yet.
Now, I did change my rims to 17" with the tire size that matches my old tires to -3% in size (so not much difference) for a winter tire. That being a heavier tread compaired to stock I guess. I do know it is colder now (coldest so far was only -9C), and I gave it few minutes of warm-up before driving, all highway driving to work.
SO... I called my dealer about it today and they seem concerned about it. When I told the service rep what I was getting, he asked about driving habbits and where I get my fuel and suggested trying a different fuel supplier for comparison since I am due for a fill-up before I bring it in. With all these questions aside, he said that is still getting lower then expected milage and he wants the mechanics to have a look. What he said that they would do is: check all fluids and filters to start, then check and see if all software is up to date, also check engine diaognostic (I'm not sure what that entails, but I guess to check compression and timing?) and of course visual inspections for anything damaged or wearing early. oh yea, he said it will be under warrenty because of the nature of the inspection.
 

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update: Just got a call from the service dep, TWO new updates or "drivability flashes" installed, diagnostic showed everything else in perfect order. I donr know how the flash updates will change it to much, but I will report any MPG gains.
 

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A few things...


Diesel Engine (and gas for that matter) like it warm. They run better (more efficiently) when they are warm...so short trips in cooler weather will give you decreased mpg. Might think about covering the front grill (diesel blanket) to up mpg. You could even try cardboard to test the theory by limiting the cold air that hits the radiator.


Diesel fuel ignites under pressure/heat. You might need to add some kind of fuel additive to increase the Cetane Level of your diesel fuel. In Europe, their fuels have a better Cetane Rating. Think of it as "reverse octane"...in a gas engine you want to up the octane (to a point) to fight detonation. In a diesel, when you increase the Cetane rating...the diesel fuel detonates easier and burns more efficiently.


You can even block off your cold air intake for a bit more heat and improved mpg in the winter.


I would also contact www.GreenDieselEngineering.com and see if they have any upgrades for the stock computer. These guys know their stuff and are very familiar with these VM/Fiat Diesels.
 

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Odds are better than good that "winter fuel" is being sold where you live if you live anywhere near where the temp "might" get below 30* or so.
you will see a decrease in MPG with winterized fuel. Beats the other option...jelled fuel.
Never trust the EVIC. Hand calculate then compare the 2 numbers. As I said on another thread in the big Rams 2500/3500 diesels we call the lie-o-meters for a reason. Also, a diesel is a negative heat loss generator. Remote starting and let idle when cold will kill the mpg. When it's cold out try this. Start the truck, drive it to get it warm/hot, park and let idle for 5 minutes. Bet the temp actually drops compared to when you were driving. ie. negative heat loss generator. Diesels make heat under a load/when working. Not idling. Look up "wet stack(ing)". NOT good. and it does apply to ALL diesels.
 

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I have notice a 3mpg drop in my around town driving since hitting 4500 miles on the odometer as well. Purchased my 4x4 Larimee on 11 August, on 17 November the starter went up. They hgad it in the shop from Tuesday through Friday for a starter, went in on Friday and they said might need to keep it until the next Monday until I complained and the owner told the service department to get a starter off from a new truck. They changed it and it still would not start, later that evening they discovered it was "a corroded cable from the alternator." How a 12 week old vehicle has a corroded cable is beyond me....but I noticed when it would not start that it was throwing sparks under the hood when it did try to crank. The dash was reading "Service 4 wheel drive system" when it would not start. These new electronic systems are very questionable in their reliability in my mind.
 

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Discussion Starter #15
I'm going to schedule a service appointment. I'm cringing because of all the stuff I've read on here. I noticed my tach was reading higher than it should at times when the EVIC was showing poor fuel mileage. I'm thinking the transmission is doing something funky, but I'm not getting any CEL or malfunction of any kind. I'm hoping they get me another truck while they play games with mine, but who knows...


Oh, one more thing - here in this part of TX, there is no such thing as "winter fuel". Its the same year round.
 

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You know, when we use the defroster in cold weather it fires up the compressor the same as if we were using the the air conditioning. Gotta keep that thing off unless the window is fogged up. You can tell cause the light comes on on the hvac control knob (depending on which system you have).

That could affect fuel economy a bit.

Just another item you probably don't use in Texas.
 

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Discussion Starter #17
You know, when we use the defroster in cold weather it fires up the compressor the same as if we were using the the air conditioning. Gotta keep that thing off unless the window is fogged up. You can tell cause the light comes on on the hvac control knob (depending on which system you have).

That could affect fuel economy a bit.

Just another item you probably don't use in Texas.


Hey Zoomie,
I used the A/C constantly when I bought this in Aug. Now that its cooler, I'm not running the A/C half as much & I think I've used my defroster twice...maybe. This morning a did the remote start as I was getting ready & the cab smelled like diesel exhaust, but no smell outside! I'm getting the feeling that this truck has a bunch of crap wrong. I'm getting 20.5 highway now. Still no warnings...is it going to surprise me or what? I would dump this at the stealership today, but I really need it this weekend. Any pointers on getting a truck for a loaner?
 

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20.5 average is nothing to be upset about in a half ton truck. My dad's hemi ram ( & he drives like an old guy ) is in the 14 mpg range. Slight variances in driving play huge in the per tank average. My tank prior to my last was 19.7 average hand calc. That was alot of city driving though. Last fill was 23.3....mixed hwy / city hand calc. And I'm sure they are running the winter blend around this part of the country.

Hershey, that 20.5 per evic?
 

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To add to it....my last fill I reset my display economy as I always do. From the station to home is basically all highway. Pulled in my shop and shut her down @ 28.4. Next day just during the warm up I was down to 20.7. Point is, the longer you wait to reset your fuel economy display the less it drops due to a longer average. For instance that decrease wouldn't have been as dramatic if I had never reset it from new. But since I just reset it 12 miles prior to shutting it off, that is the only comparison it has to go by for an "average". The only accurate way to do this is hand calc when you fill up. That will give you the truth.
 

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To add to it....my last fill I reset my display economy as I always do. From the station to home is basically all highway. Pulled in my shop and shut her down @ 28.4. Next day just during the warm up I was down to 20.7. Point is, the longer you wait to reset your fuel economy display the less it drops due to a longer average. For instance that decrease wouldn't have been as dramatic if I had never reset it from new. But since I just reset it 12 miles prior to shutting it off, that is the only comparison it has to go by for an "average". The only accurate way to do this is hand calc when you fill up. That will give you the truth.
agreed. Remote start-0- MPG. colder outside temps uses more fuel until warmed up. EVIC=lie-o-meter. feel good gauge (when you see super high MPG's.) As you said leave the EVIC ALONE/don't believe it. Hand calc only at fill up and NEVER reset the EVIC. It will get closer the longer/larger the data sample is. anything else is just a guess be it the EVIC or the owner.So far as the exhaust smell IF there are no leaks in the system and the remote start is used. I'll bet the heater was running wide open. Unless it was on Recirc. the heater draws air from outside the truck and diesel exhaust is more noticeable (pungent) than gasser exhaust. Especially when it's cold. Happens to me on the VERY few occasions I let my truck "warm up" in the winter.
 
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