MPG drop, power loss...but no CEL...

[Jet mech]

For the last few weeks my MPG went from 40mpg on the hwy down to 33 and it seems like i have a boat anchor attached to the back of my car. I drive from Louisville to Birmingham and Louisville to Michigan and for the last 10k ive always got arround 40mpg. I dont have any check engine light and the car idles fine. I brought it to the "Stealer" for the 10k free oil change and told them about the issue and they said its because of the cold temps and if i had a problem the CEL would be on. I always buy my fuel from the truckstops on the fwy so i dont think i got any crappy fuel. If i had i would feel that it would have worked its way out since i only fill up when the fuel light comes on. Has anyone else had this type of issue? I could see a small drop in MPG because of it being colder now but not such a big drop and what feels like a power loss.

 

[Tweak3D]

For the last few weeks my MPG went from 40mpg on the hwy down to 33 and it seems like i have a boat anchor attached to the back of my car. I drive from Louisville to Birmingham and Louisville to Michigan and for the last 10k ive always got arround 40mpg. I dont have any check engine light and the car idles fine. I brought it to the "Stealer" for the 10k free oil change and told them about the issue and they said its because of the cold temps and if i had a problem the CEL would be on. I always buy my fuel from the truckstops on the fwy so i dont think i got any crappy fuel. If i had i would feel that it would have worked its way out since i only fill up when the fuel light comes on. Has anyone else had this type of issue? I could see a small drop in MPG because of it being colder now but not such a big drop and what feels like a power loss.

I'd also take into consideration that most places now have winterized fuel, which can aslo add to the problem. Just a thought.

 

[snagster]

Winter diesel!! I am experiencing lower power too. I can also tell from my F250 7.3L diesel. Winter fuel sucks!

 

[RPS99SHO]

Me 4. This sucks. But comes with the territory I guess.


~ Roman

Sent from my iPhone using Tapatalk

 

[Mark_Seis_JSW]

I've noticed about a 2-3 mpg decrease in the past month guess it is what it is

 

[philisophe]

Ive always added the Standadyne...

When I failed to install the four ounces..I noticed the engine runs a little rough..

Also the temperatures here are falling into the 10's..

As they have changed over to the winter fuels...its something you may want to review..



http://www.stanadyne.com/view.php?id=74

 

[glennco]

We've noticed a decrease as well. From around 43mpg, down to 37.

 

[Timujin]

I saw a decrease in MPG on a recent trip from SoCal to Chicago. Temps varied from 17F to 67F AVG temp in the 40s. I also noticed a green tint to the D2 in the states along I40 and I44 starting in New Mexico all the way to Illinois.

 

[740GLE]

Also the warm up times are longer. I notice my normal mileage when drove home from thanks giving temps were in the 30s, but after 180 miles, mpgs were in the upper 40s.

Drive em more!!!!

 

[nhdoc]

Also the warm up times are longer. I notice my normal mileage when drove home from thanks giving temps were in the 30s, but after 180 miles, mpgs were in the upper 40s.

Drive em more!!!!

Yes, this is absolutely correct. If you do short runs on a cold engine in the winter your MPGs will be very low. Winter fuel will cut your MPGs by around 10% plus the added time it takes to achieve full operating temps will take another bite. I used to see 40 MPG average and now am seeing 35-36.

The only other comment I can make is while my mileage has dropped I don't see a huge reduction in power...slight when cold but once warmed up I can't say my car is slower now than on summer fuel. The OP's comments on performance have me concerned that he might still have a problem - maybe a boost leak - that is being overlooked. Did the dealer scan with VAG-COM? It can store codes even without throwing a CEL.

 

[740GLE]

Good point, I also haven't noticed a power drop soon as the temp needle moves, the power still seems there as always.

 

[Jet mech]

Thanks for everyones responses.

I figured i would get a MPG drop with the colder weather and different winter fuel mix but it seems large and i drive very long distances so the warm up times should not matter to much. The "Stealer" did not check anything because he said if there was any problems i would have a CEL. Im going on another long trip today (Louisville to Birmingham) and will see what my MPG and power is like and if its still crappy then i will make an appointment with another VW dealer and hopefully they will look better to make sure there is nothing wrong.

 

[nhdoc]

Thanks for everyones responses.

I figured i would get a MPG drop with the colder weather and different winter fuel mix but it seems large and i drive very long distances so the warm up times should not matter to much. The "Stealer" did not check anything because he said if there was any problems i would have a CEL. Im going on another long trip today (Louisville to Birmingham) and will see what my MPG and power is like and if its still crappy then i will make an appointment with another VW dealer and hopefully they will look better to make sure there is nothing wrong.

Sounds like a plan...I would say if your power is noticeably lower then you have something wrong...has it been over more than one tankful? You might just have gotten a bad tank of fuel. If it is recurring then you should have it checked out because significant power loss is not typical nor normal in colder weather.

 

[crashtested]

Winter fuel?

I've seen a drop in MPG this tank (1/2 way through) but no noticeable power loss.

 

[MyAvocation]

I also noticed a green tint to the D2 in the states along I40 and I44 starting in New Mexico all the way to Illinois.

Yup, IL D2 is greenish (and much of the Midwest). Was nervous filling up at a Detroit area station known for inexpensive D2, but fuel is clear as moonshine so steering clear.

 

[DanG144]

I would check for dragging brakes. Ensure your e brake cable is not binding. Look for hot rotors and hubs.
Also check your front end alignment - just ensure your tires are not wearing funny.

 

[robertsparker]

I thought I was losing some power on my 45 mile commute along with slightly lower mileage on new winter fuel.. I accounted for the sightly less power from my overzelous desire for higher mpg, by running lower rpm, lower shift points and thought maybe the variable turbo splines might be getting a little sticky... So on my next on ramp ran through to redline a few times and execised the motor a little from full stops to 3rd gear runs... After doing so seems like the power respone is norrmal again..

 

[roadhard1960]

I need to check my tire pressure tomorrow morning as the temp has dropped again. My mileage has dropped a bit. After I replaced seals on the fuel pump last week my VagCom show some error codes that did not trigger a CEL. I cleared those codes. I need to check with Vagcom to see if they came back. I generally do 44 mile one way drives and it takes 7 miles for the water temp to get to normal which is a lot longer than summer driving.

 

[Norm0770]

I've noticed my milage went down dramatically with the cold weather. I was getting 37-39 on my city street commute, but today with a temperature of -15 C I got 28.

I have been driving diesels since my parent had a 1987 Golf with the 52 hp engine and I have NEVER seen a drop in miliage this dramatic. 3-4 mpg over the length of a tank of fuel, which would equal about 10% for our 2004 Golf, but 10 mpg? That's 25%!! I'll have to see what the whole tank works out to but right now I'm pretty disapponited. I want the 1.6 TDI from Europe... I don't need all of the power of the 2.0.

 

[ultranaut]

My MPG declined noticeable with the cold weather. I got it back up by driving more gently during the warm up period and then driving it hard in sport mode for at least 15 minutes a day, typically at the end of my commute. Essentially I've gone back to driving more like I was when I was breaking her in. I usually cruise control in the 60 to 70 range so I think she gets bored and needs it a little rough to keep her happy.

 

[ihatespeed]

kerosene issues

I too noticed a -5 drop in mpg, figured winter fuel.. according to Gulfs website they use something other than kerosene to blend their cold weather mix, and based on my expierience it brought my mialage right back up.

The two fillups I hit were a shell and a mobil, but I previously used gulf due to convienience

I guess my advice is don't take it lying down. find a station that is using a better solution than kerosene for a winterizer.