2009 Jetta TDI Winter FE

solartempest

Veteran Member
Joined
Mar 28, 2009
Location
Toronto, ON
TDI
2009 Jetta Sedan DSG
Winter is here! Just wondering how bad you 2009 owners are having your mileage get hit.

On a nice road trip where I expected at least 5.2L/100km (45.2MPG), I got 6.1L/100km (38.6MPG).
Mostly my mixed driving of city/highway should be around 5.7L/100km (42MPG), but I'm getting 6.3L/100km (37.3MPG). :(

Are you guys getting squashed like I am? Average temp here for this time of year is 8.4C (47F).
Running stock all season 16" tires at 40PSI, haven't switched to my winters yet.

Filling up with ESSO diesel, standard Canadian stuff. No additives.

I did get oil overfilled at my last service, but I'm figuring it's winter fuel and not related to that, reflecting upon my fuelly records over the past bit.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
just did a trip from portsmouth nh to quebec and back 700+ mi. I haven't topped off this tank yet, but i am looking for around 45 round trip which impressed me as i had a heavy foot going between the mountains Solan ME and st george.

So far even with some mixed driving and running B5 the last two tanks I've been getting 45-46. This is about 90% highway or 50+ as I pedal to work.

Every time I fill up I am glad I didn't get a DSG.
 

solartempest

Veteran Member
Joined
Mar 28, 2009
Location
Toronto, ON
TDI
2009 Jetta Sedan DSG
740GLE said:
Every time I fill up I am glad I didn't get a DSG.
I have a very short commute to work of 7km (4mi), which is barely enough for the engine to warm up.

Maybe some other owners will chime up, but I find it hard to believe that this transmission in particular accounts for such a huge difference.
I'm driving in manual mode and using neutral quite a bit, no D or S whatsoever.
 

droit

Well-known member
Joined
Apr 14, 2009
Location
Maryland
TDI
09 JSW TDI 6M
solartempest said:
I have a very short commute to work of 7km (4mi), which is barely enough for the engine to warm up.
using neutral quite a bit,
My cars burns more fuel the first 5- 9 miles.

My car uses more fuel when I put it in nuetral verses coasting gear. If I have a hill to coast down and leave it in gear it registers flat line on the MFD if I kick it into nuetral the mfd shows varing mpgs.
 

Mike in Anchorage

Veteran Member
Joined
Jan 4, 2009
Location
Anchorage, AK
TDI
2016 Touareg Lux, 2015 Golf Sportwagen SE, new 4 Sept 2017;2009 VW Jetta TDI Sportwagen (Ruby) sold to VW on 22 SEP 2017
It's a cmbination of heating up the engine as well as the fuel having less heating value. For my ast tank, I had the snow tires on and I think the fuel had already been winterized. We haad a spell of lows about -20°C with highs about -12°C. The tank avg for me was about 7.7 l /100 km. I'm not pleased, but it's a sight better than my previous cars. The tranny has little to do with it, but trip length does, and your choice of using or not using the 1 kW electric heater to warm & defrost. If you can stand it until the engine is warmed up, leave the cabin fan speed control on off.
 

Joe_Meehan

Top Post Dawg
Joined
Sep 3, 2005
Location
Ohio USA
TDI
NB TDI, 2002.5, Silver
How long your trips are will make a big difference as well how cold it gets. In very cold weather, partly blocking the engine compartment will allow the engine to get to full operating temperature.
 

DoctorDawg

Veteran Member
Joined
Aug 26, 2008
Location
Southeastern US
TDI
'09 Jetta Loyal Edition
Between 50* F and freezing (or thereabouts), on short to moderate trips (like my 23 mile commute) I lose about 8% on my FE...combination of longer warm-up time and winter diesel. On long trips, like my frequent 330 mile runs to Baltimore, at pretty much any outdoor temperature the fuel economy hit is just barely noticeable...which tells me that warm-up time takes a bigger bite than does winter fuel.

For reasons I don't fully understand, rainy/misty weather hits my FE, too.
 

itchytweed

Veteran Member
Joined
May 24, 2009
Location
Milwaukee, WI
TDI
2010 Jetta TDI Sportwagen
I would say that temperature has its hand in this as well.

Since I have had my 2010, I can tell that it behaves differently. When we had temps in the upper 50 to close to 70, the car on starting out was not that noisy. But now that the temps are getting colder (low 40's and today it is 31 out), the engine on morning startup is sounding more like an older diesel, the nailing sound is obvious until the engine warms up, then it disappears. Me thinks that the car is going to one slug of fuel at that time rather than multiple mini-squirts because the cylinders are cold and the colder intake air doesn't help things out either, so to ensure ignition, more fuel is used. I would say that this is the nature of the beast.
 

NickJ85

Member
Joined
Jul 4, 2009
Location
Rockton, IL
TDI
2009 Jetta Sedan (Manual)
I am interested to hear the effects of winter diesel as well. I purchased my 2009 Jetta Sedan 6m TDI at the end of Oct 2009. I live in Northern Illinois and commute to work in Wisconsin so I am sure I have been fueling with a winter blend. I typically get between 38mpg and 40mpg highway (hand calculated) driving between 70-75mph with some small rolling hills. I am interested to see what kind of improvement I might see when the summer mix comes back.
----------------
2009 Jetta Sedan TDI / Black / 6M
 

retro_mike

Well-known member
Joined
Jul 27, 2009
Location
t.o.
TDI
2000 Golf TDI 4Door 4A
i noticed in your original post you mentioned using Esso diesel, try using Sunoco Gold Diesel, it currently has the highest cetane rating and you should notice a fuel economy increase and the engine will feel a bit more powerful as well. I'd also recommend using a diesel fuel additive like power service or stanadyne or lubromoly, they all help keep the fuel system parts clean and will bump the cetane rating a bit higher again, also helping with FE.
For the record i'm at least 50km short on this tank of fuel so far compared to where i should be(mid november fuel up) so the winterized fuel is definitely here and poorer economy is something we're all going to have to live with for the next 4-5 months.
 
Last edited:

Thunderstruck

Veteran Member
Joined
Feb 19, 2004
Location
Chicago
TDI
2015 GTI SE 6M
Mine is louder too, and I like it! I'm not going to say I wish it never gets warm, but I kind of dig the rattle.Once I get my shudder problem resolved by the dealer I'm getting a Frost Heater installed. That should help economy immensely, at least it did on my old Golf.
 

solartempest

Veteran Member
Joined
Mar 28, 2009
Location
Toronto, ON
TDI
2009 Jetta Sedan DSG
Edit: forgot to note that this trip is my usual commute (one way), everday!


As an example of my cold weather mileage "penalty" today:
Ambient/Starting temperature was 2°C.
Most of the way was at ~56mph (80-90km/hr).
Stopped once for a light, maybe 4 turns I took easily in 3rd gear.

Total Distance:
4.6mi (7.4km)
Trip FE: 18mpg (13L/100km)
Final Coolant Temperature: 136°F (58°C wt)

Typical FE for Summer Trip like today: 42mpg (5.6L/100km)

retro_mike said:
I'd also recommend using a diesel fuel additive like power service or stanadyne or lubromoly, they all help keep the fuel system parts clean and will bump the cetane rating a bit higher again, also helping with FE.
A good point! I've definitely thought of this whenever I've filled up. Maybe I'll pick up some Power Service from Canadian Tire (not sure if there are cheaper places around in the GTA) and give that a shot. That way I'll be sure to keep my fill level consistent and see the effect of higher cetane. Right now, I've been sticking with Esso since it keeps my Aeroplan active.

Thunderstruck said:
Once I get my shudder problem resolved by the dealer I'm getting a Frost Heater installed. That should help economy immensely, at least it did on my old Golf.
How much did this help? I'm in underground parking, so I don't think I will have access to an electrical outlet. At least inside the garage it's above 6°C or so. I can always hunt for an outlet and see if I can get my spot switched =P Doesn't help me for at the office though.
 
Last edited:

Thunderstruck

Veteran Member
Joined
Feb 19, 2004
Location
Chicago
TDI
2015 GTI SE 6M
Depending on the temp out, it kept it pretty good. I don't remember any more, but it was surprisingly high. My problem is I have a 6 mile drive to work one way so the car is always running the cold weather fueling until I get to work w/o a coolant heater. The heater works on the coolant in the reservoir since the engine is not turning. You'll see the temp drop when you start, but it will get back again far quicker than a true cold start. Coolant would be at 170 at start up according to my SG.
 

barshnik

Veteran Member
Joined
Jul 14, 2008
Location
Las Vegas, NV
TDI
2013 Passat SE w/roof, nav
I'm in the best part of the year for FE - winter! No AC! I'm been doing a solid 4 mpg better than during the summer. No real reason to brag compared to most that post in this section, though, as it means 39 mpg instead of 35. However, I'm either stuck in city traffic or driving 90 mph on the highways.
 

retro_mike

Well-known member
Joined
Jul 27, 2009
Location
t.o.
TDI
2000 Golf TDI 4Door 4A
solartempest said:
Edit: forgot to note that this trip is my usual commute (one way), everday!


As an example of my cold weather mileage "penalty" today:
Ambient/Starting temperature was 2°C.
Most of the way was at ~56mph (80-90km/hr).
Stopped once for a light, maybe 4 turns I took easily in 3rd gear.

Total Distance: 4.6mi (7.4km)
Trip FE: 18mpg (13L/100km)
Final Coolant Temperature: 136°F (58°C wt)

Typical FE for Summer Trip like today: 42mpg (5.6L/100km)
Here's your problem: you don't drive far enough (7.4km) to have the engine run at operating temperature (58C final coolant temp). The whole way to work it's still on it's cold enrichment "circuit" and using extra fuel. And it will be the same on the way home too. You're just going to have to suck it up in the winter as far as bad FE is concerned. The only thing that will help is if you install a FrostHeater or something else that will keep the engine warm before the morning drive. As you stated earlier, you don't have a plug at work so this will only be effective 1 way. i'm not sure the cost/benefit equation would be worthwhile in your case but you would have toasty heat inside the car for the morning drive.
 

solartempest

Veteran Member
Joined
Mar 28, 2009
Location
Toronto, ON
TDI
2009 Jetta Sedan DSG
retro_mike said:
Here's your problem: you don't drive far enough (7.4km) to have the engine run at operating temperature (58C final coolant temp).
Yup, I just thought I'd bring a bit of my own experiences to show how much the warm-up period affects diesels, particularly with the CBEA engine. It's a little frustrating sometimes because I don't even bring the engine past 2,500 rpm some days on my commute, since I can't hit the operating temperature of 60C (third temperature tick on the gauge, I think).

Agreeably so, the installation of a Frostheater probably won't be very economical for me. Figure I might as well suck up being cold for the first 1/3 of my commute, since I'll be warm and toasty in the office/home about 10 minutes later =P

It's a hard mental game though! Putting my mileage info into the "X Month Mileage Threads" is a bit depressing. :cool:
 

MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
Total Distance: 4.6mi (7.4km)
There's another factor.....do you have the heater dial turned all the way up to hot? Until the coolant reaches a certain temperature, there's an electric heater element in the cabin heating system that's putting a heavy load on the alternator. This will reduce your mileage significantly.
 

solartempest

Veteran Member
Joined
Mar 28, 2009
Location
Toronto, ON
TDI
2009 Jetta Sedan DSG
MayorDJQ said:
Until the coolant reaches a certain temperature, there's an electric heater element in the cabin heating system that's putting a heavy load on the alternator. This will reduce your mileage significantly.
I always leave the temperature dial set a bit below the middle marking, which I think is 22C (72F)? I also leave the fan/defrosters off, since I never need them in the morning and very rarely have any fogging issues on the way home.

Does the electric heater only turn on when you crank the temperature to max with the coolant cold?
 

MayorDJQ

Top Post Dawg
Joined
Dec 4, 2001
Location
Williamstown, Mass
TDI
'10 Golf 2dr 6m, sold.
solartempest said:
Does the electric heater only turn on when you crank the temperature to max with the coolant cold?
I believe so. If you turn off the radio and set the fan to low, you should be able to hear a noticeable CLICK when you turn the temp dial up to max. You should here another click if you turn the temp back down.

I don't recall the numbers, but one morning I hopped on the interstate a few miles from my apartment. I had the cruise set at 55, MFD set to instantaneous mileage, and when the electric heater kicked in/off the number fluctuated greatly. It dropped below 30mpg with the heater on.
 

jbright

Veteran Member
Joined
Sep 10, 2009
Location
Indianapolis
TDI
2009 Jetta DSG
We just had our first day of what I would call winter weather. I definitely noticed a big difference at 28 degrees versus the warmer temps we've been having all November. It took me a lot longer to hit 40 mpg on the MFD, and I noticed my instantaneous readings were off too. I went for my daily run and my body suffered the same negative effects as my engine. However, on my drive home from the running trail I reset my MFD and my mpg rose into the usual range very quickly, just a few minutes (I drove on the freeway for 20 minutes to warm the car up and hit 40). I'm pretty sure I don't have winterized fuel yet.
 
Last edited:

BleedingDiesel

Well-known member
Joined
Oct 8, 2009
Location
Ontario, Canada
TDI
2001 Jetta
Solar, The Esso's near my part of town just north of T.O only have Low Sulfur Diesel. I dunno if it makes a difference but the Ultra Low may be a better purchase for only pennies more from petro can. or Shell
 

pburger

Well-known member
Joined
Jul 14, 2009
Location
Perrysburg, OH
TDI
2009 Jetta TDI
09' Jetta is averaging about 38 now that it's cooled down in NW Ohio. 150 round trip daily to Detroit and it used to be about 40 mpg.
 

chops_555

Veteran Member
Joined
Jul 29, 2008
Location
Texas
TDI
09 Jetta TDI 6spd manual Build date: 09/08
Yeah same for me. I have about a 30mile commute about every day and I have noticed a drop to about 39 as opposed to about a 41-42 on the highway. However, some of it is to do with our garage door is broken and every car we have is outside now and I sometimes have to start the car and let it idle with the defroster on thus dropping my average some while I wait.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
on my 45 mile commute to my girlfriends, i was able to see 52 on the MFD both ways, this past monday when it was 18 out when i started i could only get it up to 45 and that was really trying hard.

I am going to have to try it with out the electric heater see what happens.
 

Thunderstruck

Veteran Member
Joined
Feb 19, 2004
Location
Chicago
TDI
2015 GTI SE 6M
TDI drivers are the only group of people that use the words only and 45 MPG in the same sentence.
 

TornadoRed

Top Post Dawg
Joined
Aug 3, 2003
Location
West Des Moines (formerly St Paul)
TDI
2003 Jetta TDI wagon, silver; 2003 Jetta TDI wagon, indigo blue; 2003 Golf GL 5-spd, red (PARTED); 2003 Golf GLS 5-spd, indigo blue (SOLD); 2003 Jetta TDI wagon, Candy White (SOLD)
DoctorDawg said:
Between 50* F and freezing (or thereabouts), on short to moderate trips (like my 23 mile commute) I lose about 8% on my FE...combination of longer warm-up time and winter diesel. On long trips, like my frequent 330 mile runs to Baltimore, at pretty much any outdoor temperature the fuel economy hit is just barely noticeable...which tells me that warm-up time takes a bigger bite than does winter fuel.
TDIs use up to twice as much fuel during the warmup period as they do after the engine reaches normal operating temperature.

So the car that makes many short trips during cold weather will get worse fuel mileage than one which makes one or two long trips each day, ceteris paribus.

Naturally, the colder it is then the longer it takes for the engine to warm up. How far you drive after the engine is warm determines the overall fuel economy penalty.
 

Fencemaker

Veteran Member
Joined
May 12, 2006
Location
Washington, PA (SW PA)
TDI
2006 Jetta TDI 5sp; 2009 JSW TDI 6sp
Originally posted by Joe Meehan
In very cold weather, partly blocking the engine compartment will allow the engine to get to full operating temperature.
Here is a link to a winter cover for the A5 (at $248 CAN, it's kind of pricey given that it might only yield you an extra 1-4 mpgs for 3-4 months a year):

http://www.southlandvw.ca/dcm2/parts_specials.html

In addition, there is a guy in Manitoba (lots colder than where I live in PA) that is reporting here on the Forum on his experience with a similar winter cover on his 2009 Jetta TDI (so far, he doesn't see any impact on DPF regen operation - as some have suggested might occur):

http://forums.tdiclub.com/showthread.php?t=266637

If you get one of these, please let us all know how it works out (I've been thinking about something like this for my 2006 for quite some time, but haven't pulled the trigger to date).
 

1953randy

Active member
Joined
Nov 14, 2009
Location
warrenton,mo.
TDI
2010 jsw--turned in 1-17--now 2017 Passat SE w/Tech
Thunderstruck said:
TDI drivers are the only group of people that use the words only and 45 MPG in the same sentence.
Yeah,and I'm proud to be a tdi'r since 2002 and a full time diesel driver since 1981.
 

jbright

Veteran Member
Joined
Sep 10, 2009
Location
Indianapolis
TDI
2009 Jetta DSG
12 F this morning. Car started right up. I had to drive 30 miles, mostly on freeway and suburban sprawl highway. 37 mpg. On the trip home, same route, speed, temp, etc, I got 46. This is my first tank of winter fuel. I'm pleased. This '09 at least seemed unfazed by the cold.
 
Last edited:
Top