FE to expect from 2.0 CR TDI?

buyingconstant7

Veteran Member
Joined
Jul 13, 2014
Location
Calgary, Alberta
TDI
2006 Jetta TDI 5spd
I purchased a certified pre owned 2013 Jetta TDI 6spd just two weeks ago. I filled up once so far, and with the dealer fill, I got a somewhat underwhelming 38mpg(6.2 l/100km) in my all highway commute. I was expecting at least low 40's just because I don't idle the car, I drive for economy, A/C is never on, and my tires are above the recommended PSI rating. My MFI computer is saying about 41mpg on the extended period mode. I am keeping track of regens on my scan guage and it's done 3 in two weeks(600 miles). I came from a 2015 Golf 1.8t which got the EXACT SAME mileage. I bought this car because of my longer highway commutes, lower ownership costs, lower payments and better fuel economy, but yet, this car seems to be costing me the same as my Golf was. Is there something wrong with the car, or is this normal economy?
 

jerryn63

Well-known member
Joined
Oct 17, 2012
Location
Swansea, MA
TDI
2014 Beetle TDI
Alberta-- isn't it cold outside ?

when it's cold diesel is blended with anti gel and kereosene. mpg will take a hit. I still achieve 43mpg during the commute to work.
During the spring you will see at least 25% improvemnt.. unless the emissions fix reduces overall efecciency.
 

jerryn63

Well-known member
Joined
Oct 17, 2012
Location
Swansea, MA
TDI
2014 Beetle TDI
Here's what I get with my 2014 TDI

It's cold outside.. 28F (-2C).. winter diesel blend out now..
18 mile commute average 50mph. ---- 42mpg

recent roadtrip (October 2015)300 mile drive to Bartlet, NH 62mpg

It's going to warm up today to at least 10C. .. I expect to get around 44mpg


What was the air temp when you noticed the 38mpg ? Were you running winter blend diesel ?

Get some cetane booster and add that to 1 full tank of fuel... flush it out.
Maybe the previous owner ran #2 diesel ? Biodiesel ?
 

dbias

Veteran Member
Joined
Jan 24, 2015
Location
Huntington WV
TDI
2015 Passat SE w sunroof buyback 3/18/17
I purchased a certified pre owned 2013 Jetta TDI 6spd just two weeks ago. I filled up once so far, and with the dealer fill, I got a somewhat underwhelming 38mpg(6.2 l/100km) in my all highway commute. I was expecting at least low 40's just because I don't idle the car, I drive for economy, A/C is never on, and my tires are above the recommended PSI rating. My MFI computer is saying about 41mpg on the extended period mode. I am keeping track of regens on my scan guage and it's done 3 in two weeks(600 miles). I came from a 2015 Golf 1.8t which got the EXACT SAME mileage. I bought this car because of my longer highway commutes, lower ownership costs, lower payments and better fuel economy, but yet, this car seems to be costing me the same as my Golf was. Is there something wrong with the car, or is this normal economy?
A large bit of the disappointment may come from the "dealer fill". If the quickly filled it and foamed it up and stopped there and you filled it fuller then that will cause a lower MPG number.
 

jason_

Veteran Member
Joined
Jun 2, 2014
Location
michigan
TDI
2015 s wagon dsg
What?

Waiting for foam to settle and squirting a few more dribbles makes more mpg?

We're measuring miles per gallon, not miles per tank? Right?

Sent from my One using Tapatalk
 

Lincoln

Veteran Member
Joined
Jan 14, 2014
Location
Seattle, WA
TDI
2013 Passat TDI SE 6 Speed MT
Wait a bit before panicking. You should go through multiple full tanks before trying to get a feel for your true mileage (hand-calculating, rather than reading the MFI). I'm guessing it's a bit higher than your early indications.

But even assuming the initial indication is correct for your mileage, it's probably due to the cold weather (less efficient), winter blend (lower cetane), and driving habits (learning "feel" of what the new car "likes" compared to your old golf). Assuming your commute is 20 miles each way (based on 600 miles in 3 weeks), you should probably wind up in the lower to mid 40s in current conditions. Maybe even upper 40s in the summer.
 

UFO

Veteran Member
Joined
Jul 31, 2007
Location
A mile high
TDI
2001 Beetle
Cold weather effects on mileage really add up.

Winter fuel has less energy density.
The engine takes longer to warm up after starting.
Cold air is denser, and presents more aerodynamic drag at speed.
Mechanical links and resistances are less efficient when cold (tire sidewalls, gears, CV joints).

I agree with previous posters, monitor mileage and see how it settles out, and check it again in the spring.
 
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