tips for fuel economy

Midwest snowball

New member
Joined
Dec 24, 2017
Location
Ohio
TDI
2013'jetta
Snow flap recall

Umm. This will drastically effect your fuel economy. Even though the service tech and the manager both swore it would not. I used to love my TDI that got 46 mpg. Now I have an overpriced piece of junk that barely gets 29 mpg. The only difference, one stupid recall. Just say no.

Now my engine light is on and the code is PO48C. Apparently something to do with a flap. Does anyone know if this is related? I went from VW lover to hater all because of this crap!
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
LOL, you guys kill me. Seriously, if any 4 cyl TDI was getting 29 MPG you'd have a constant black cloud following you around. There simply isn't any way the engine could consume that much fuel. Or you have a fuel leak.
 

leicaman

Top Post Dawg
Joined
Dec 24, 2004
Location
Sheboygan, Wisconsin
TDI
2015 Golf TDI SE, 2005 TDI GLS, RIP
The tire is more apt to deform and cause more rolling resistance if it is not of the proper load rating.
Brian is absolutely right. My dealer many years ago tried to sell me a set of tires that had a load rating of 89 when my B5.5 at the time needed a load rating of 91.

I told him, ah no. Went to my favorite tire vendor, who is a about 8 blocks from my house and he got me what was required. I really believe that some do not understand the load rating system. Do not forget that if you get into an accident and it is considered your fault and they find your tires are not the right load rating, that could get you into trouble.
 

Fletcher

New member
Joined
Mar 9, 2017
Location
OLYMPIA, WA
TDI
2015 Passat TDI SEL DSG; 2013 PASSAT SE manual
Mileage

I have recently gone from a 2013 TDI SE manual transmission that was averaging 43 mpg city and highway combined to a 2015 "fixed" TDI SEL Premium that is getting approximately 33 mpg city and highway combined; a 25% drop in mpg. This is much worse mileage than I expected since much of the information out there including from VW is there may be nothing to about a 12% loss of mpg as a result of the "fix". The 2015 has about 30,000 miles. My 2013 which I was planning on doing the buyback has 75,000 miles. Can anybody offer any encouragement to me for possible improving the mpg on the 2015? Are there others that are experiencing this low of mpg on their fixed 2015 TDI SELs? It's really been affecting my sleep.
 

Fletcher

New member
Joined
Mar 9, 2017
Location
OLYMPIA, WA
TDI
2015 Passat TDI SEL DSG; 2013 PASSAT SE manual
mileage

Umm. This will drastically effect your fuel economy. Even though the service tech and the manager both swore it would not. I used to love my TDI that got 46 mpg. Now I have an overpriced piece of junk that barely gets 29 mpg. The only difference, one stupid recall. Just say no.
So could this be why I'm only getting a mere 33 mpg city and highway combined with my "fixed" 2015 TDI Passat SEL DSG? I doubt that it will even meet the 30 city 42 highway EPA ratings.:(
 

DieselSport15

Member
Joined
Feb 27, 2018
Location
Kansas
TDI
2015 Sportwagen SEL, 2014 Touareg Exec.
Man, I must either be a horrible driver (which I'm not) or my car for some reason my car is really hurting!! I see all these posts of guys averaging 48+ mpg and getting 600+ miles a tank... I have a 2015 GSW DSG with about 14k miles and I don't know if I have ever seen better than about 38-40 actual manually calculated mpg and that is probably 90% freeway driving at 70-75 mph! :( :( :( Guess I'm going to have to hit the suggested list of things to check.
 

Jetta_Pilot

Top Post Dawg
Joined
Apr 14, 2005
Location
West Hill, Ont. Nov.2nd in Mexico till April 27th
TDI
2015 Passat Highline TDI Candy White (SEL Premium) long gone 2002 Jetta TDI
I've said it before, in my opinion there are a lot of dreamers around here. They drive 80-90 Mph and claim to get 50 Mpg or more.

I average just over 70 Mph on freeways. I also religiously record EVERY fill-up, filled to the top of the neck and my average Mpg is around 40 Mpg US.(approx. 50 Mpg Imperial)
 

Tom Servo

Veteran Member
Joined
Jul 9, 2000
Location
LA (Lower Alabama)
TDI
2005 Gol TDI, blue and falling apart
There are certainly some folks on here whose claims I'm skeptical of, but even if you dismiss some of the more outlandish claims, these engines do seem to have a pretty wide range of averages as far as mileage goes.

Personally, I think it's just that these cars are more sensitive to tiny changes than something that gets, say, 20 mpg. And frankly, I think they come from the factory with a lot of variance, as there's people with identical setups (manual, same driving habits and speeds) that have 5 or 10 mpg difference in MPG and can't figure out why. It's just a mystery. At least to me.

I know in my own case, I saw a pretty dramatic drop in overall mileage over the course of just a few months, and never could pinpoint it on any one thing. For the first eight years or so of my car's life, it got a rock solid 47 mpg average. It's a Golf BEW with a manual, for what it's worth. During that time the range from tank to tank was anywhere from 39 (a road trip to California) to 54 (back roads in Mississippi) MPG.

Now, the average is about 40 MPG. Summers it's 37-40, and winters it's 39-42 MPG.

All the routine maintenance is done on schedule, so I ruled out clogged filters or suspension/brake problems.

Around the time the drop happened, I began routinely schlepping two other rather large passengers around. And I've certainly put on weight, myself. Plus, I got cheaper tires that were not the eco-friendly Michelins I'd had before. The timing belt was also done at a dealer and who knows what those people did. And now I'm in a different area than before, so traffic is 100% city with speeds rarely exceeding 55 for long. And I run the A/C almost year round because of the warmer, more humid climate at the beach.

Best I can tell, it's a combination of "all of the above" that caused the mileage to crater. While a 7 MPG drop is alarming to us, that's just 15%. In a car getting 20 mpg, that's like dropping to 17. I bet a lot of drivers wouldn't even comprehend that.
 

Jetta_Pilot

Top Post Dawg
Joined
Apr 14, 2005
Location
West Hill, Ont. Nov.2nd in Mexico till April 27th
TDI
2015 Passat Highline TDI Candy White (SEL Premium) long gone 2002 Jetta TDI
It is a proven fact, regardless of whether you are driving a gasoline or Diesel powered car, your absolute best mileage (Mpg) is obtained at a steady speed of between 50 - 55 Mph. Once you go above this threshold your Mpg suffers.

Just look up how professional Mpg testers do it. No high speeds, no AC, no jackrabbit starts, no sudden braking and they drive as if they have a raw egg between the foot and the pedals!
 

h4vok

Veteran Member
Joined
Feb 4, 2017
Location
Denver (ex MN)
TDI
2003 Jetta TDi 5sp 171k
For my mileage keeping it under 70mph and the ambient temp are a huge factor in my mpg. For example I just got back from Texas. I recorded 2 49mpg tanks down there and my speed was around 70mph. The temp was about 75f so I didn't need AC, but was still nice and warm. As I headed north my mpg dropped slowly as I started to maintain about 80mph and the temp dropped to the 30s. At this point I only got about 43mpg. When I am in MN I normally do about 70mph and record low 40s in winter and upper 40s in summer so on par with what I recorded in TX. My car is only lightly modded with a straight pipe, DLC520 and a tune. I don't baby it around, but I also avoid using the brakes and coast some. The cruise control is something I use a lot too that seems to help, but never use the accel button reset it yourself. The cruise is extremely aggressive when using the accel/resume.
 

longnow

New member
Joined
Sep 14, 2017
Location
seattle
TDI
2015 Golf TDI S
Driver behavior is behind variance in fuel efficiency. You can test yourself and find the sweet spots of your car by switching the MFD to display current consumption. The number changes as you drive. You'll notice a big difference in consumption with slight variance in pedal-pressure, but the car doesn't perform much different. You can be going 40 MPH on flat road and doing 60MPG on the consumption meter, or you may see 38MPG on the same stretch. The difference is if you are accelerating, coasting, or steady cruising. Each of those drive modes has totally different consumption. So find where you get better performance and stick to that.

I drive about 40 miles per day round trip, and that is 85% highway. The highway portion of the trip is not though, at full speed, as in Seattle traffic is terrific. My average speed is typically around 35mph over a full tank. Temperatures are mild in the Northwest. There is often water/rain during the winter here.

My average tank this winter has been around 49MPG.
The average in the Summer/Fall is around 51MPG.

I can attribute much of the difference here to rain/water on the streets that add to drag and road friction.
 

DieselSport15

Member
Joined
Feb 27, 2018
Location
Kansas
TDI
2015 Sportwagen SEL, 2014 Touareg Exec.
The calculator on my dash (I know they are not known for being accurate, although in my Touareg its pretty spot on) was showing on my last trip at 3/4 of tank used, Average Consumption = 66.8 When I finally fill up at 590 miles, I do a manual calculation and I'm only at 49mpg. Really???? 15mpg discrepancy??? You guys that are showing 50+mpg, what size wheels are you rolling? I have stock 18s on my SEL and I'm on a Kerma tune. I just don't see how its possible to break 50mpg. ???????
 

Jetta_Pilot

Top Post Dawg
Joined
Apr 14, 2005
Location
West Hill, Ont. Nov.2nd in Mexico till April 27th
TDI
2015 Passat Highline TDI Candy White (SEL Premium) long gone 2002 Jetta TDI
The calculator on my dash (I know they are not known for being accurate, although in my Touareg its pretty spot on) was showing on my last trip at 3/4 of tank used, Average Consumption = 66.8 When I finally fill up at 590 miles, I do a manual calculation and I'm only at 49mpg. Really???? 15mpg discrepancy??? You guys that are showing 50+mpg, what size wheels are you rolling? I have stock 18s on my SEL and I'm on a Kerma tune. I just don't see how its possible to break 50mpg. ???????
I take all these high mileage claims with a large dose of skepticism!

There are claims of doing over 80 Mph and getting 65 Mpg ? Maybe going downhill?

My former Jetta with the 01 auto was giving me about 43 Mpg on average over the many years I had it.

My current Passat with the DSG is about 41 Mpg since I bought it 2 years ago. The ONLY time I ever hit around 80 Mph is in Texas on a toll road bypassing Austin and San Antonio. Otherwise my normal highway speeds are keeping up with other traffic!

With both cars I enter EVERY fill-up into an APP on my iPhone !
 

dubStrom

Veteran Member
Joined
Aug 6, 2007
Location
Kansas City Missouri
TDI
2003 A4 Jetta (sold), 2010 JSW (sold), 2013 Passat 6MT traded for 2014 JSW with 6MT-TOTALED in November 2016, 2003 ALH 5MT conversion (sold), NEW 2015 GSW/DSG and an '07 Ram 6.7L Cummins Turbo Diesel quad-cab Laramie 4x4 p'up
-Be 'that guy' who drives the speed limit and stay in the right lane so people can go around you. If you are coasting to a stoplight, let others go around you. Be ready for the dreaded stare at the red light, because you will likely see the person who flew around you at the stoplight sitting next to you. :rolleyes:
Now this is really funny. But seriously, most drivers on the commute to or from the 'burbs accelerate immediately to the speed limit, or push to the speed limit plus 4, or plus 9, depending on how the radar slingers in your area parse it.

Well, I push the limit, but my acceleration depends on hypermiling considerations, not the speed limit on the other side of the intersection!! most of the time I get to the "speed limit" when the hypermiling rules allow me to. And yes, as Brian sez, let it gradually slow down on the way up hills (especially if the hill is steep enough to push the MPG down trying to hold speed), and let it drift upwards slowly on the downhills after you peak the hill. It is one of the "haulmarks" of top notch hypermiling, and it take gradual and deliberate changes to foot pedal position (while glancing at the instantaneous MPG readout). But this behavior drives "speed limit" type drivers nuts. It is understandable... You catch them and maybe pass, then they pass you on the way up the next hill. You can see them boiling over wondering what the heck is wrong with your car, or the driver.

But on the commuting arteries, even if you are in the right lane, people pass you like you are doing something wrong around here if you are going the speed limit. And they can be downright dangerous! It is frankly much safer to drift up to the "real" speed limit. It can easily be done while hypermiling. It just doesn't happen as fast:rolleyes:

Leave more than one and a half car length in front of you (even above 50 mph and up!!), and expect to have someone take that "position". It happens like gravity pulls the apple to the ground in the Fall.
 
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Tom Servo

Veteran Member
Joined
Jul 9, 2000
Location
LA (Lower Alabama)
TDI
2005 Gol TDI, blue and falling apart
I feel for ya, dubStorm. That commuter behavior would drive me crazy. I live in a tourist area and don't keep 9-5 commuting hours, thankfully, so that stuff is in my rearview mirror, so to speak. Around here, the roads are nice and open during short periods between the snowbirds being here in the winter and the Spring Breakers, then summer tourists from Memorial Day to Labor Day. During those times, it's bumper to bumper and you're lucky to even get within spitting distance of the speed limit.

That certainly makes being "fuel friendly" more difficult. I'm curious though as to which works better when approaching red stoplights: Coasting out of gear to a stop, or using engine braking. Coasting is possible when traffic is light around here, but I find using engine braking a little more useful in moderate traffic. It sure does tick off tailgaters though, "slowing down without using brakes, what is that sorcery!" :D

At least that's the look they seem to give as they go to pass, ha ha.

Having said all this, and cognizant of the fact that this is a fuel economy tips thread, I gotta say… I do tend to like to get where I'm going as fast as reasonably possible, so sometimes I'm "that guy" passing the slowpokes. But as long as they are in the right lane and leaving me space to go around, I'm cool. The left lane lolligaggers are the ones who really tick me off. (Along with tailgaters, the inattentive texters and the motorcyclists who ride like they're trying to kill themselves.)

The nice thing about these TDIs, is you CAN drive like a regular person and still get great mileage, and eeking out a few extra MPGs on top of that is not too difficult, either.
 

dubStrom

Veteran Member
Joined
Aug 6, 2007
Location
Kansas City Missouri
TDI
2003 A4 Jetta (sold), 2010 JSW (sold), 2013 Passat 6MT traded for 2014 JSW with 6MT-TOTALED in November 2016, 2003 ALH 5MT conversion (sold), NEW 2015 GSW/DSG and an '07 Ram 6.7L Cummins Turbo Diesel quad-cab Laramie 4x4 p'up
...

The nice thing about these TDIs, is you CAN drive like a regular person and still get great mileage, and eeking out a few extra MPGs on top of that is not too difficult, either.
Yep. We get the torque and FE too! Secretly, us stealthy turbo diesel owners get 20%-30% more miles per gallon, at 10% higher fuel prices. And low end usable torque. In practice, we get measurably better performance in usable driving conditions, while getting farther on the same amount of fuel.

On the question of "coasting"...I keep it IN GEAR when slowing down to a stop. I don't have a clutch, but when I did, I did NOT put it in neutral. If it is in gear, the fuel delivery is shut off when "coasting in gear" to a stop (zero mpg during engine breaking). That can't happen if your car is idling (coasting in neutral), so you use more fuel.

Considering how sophisticated these things are now, TDIs must do that. How could VW engineers fake emissions but NOT take advantage of PZEV?! That PZEV sign on Subarus means fuel shut off when engine breaking (even if you add friction braking). That's "Partial Zero Emissions Vehicle".
 
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mike837go

Member
Joined
Nov 20, 2018
Location
MetroNY
TDI
2014 Jetta Sportwagen
My 2013 Jetta sedan got 43-48 MPG from the time I bought it new until it was bought back.

I just bought a post-fix 2014 Jetta SportWagen. All 6 tankfulls so far have been 39.5 MPG.



Same routine use. Same basic (poor) driving habits. Both cars are 6-speed manual.
I know the JSW is a heavier car and the fix would impact mileage as well.


If I decided to drive a bit slower, take it easier when leaving a stop, etc. I could see 42+ MPG on the new car.



But the darned thing is so fun to drive!
 

darren65

New member
Joined
Dec 17, 2018
Location
NY
TDI
2.0
Found here a lot of good tips on how to save on fuel, thanks! After all, as a student, it is so important! I will spend the saved money better for acquiring an essay, for example. I often go to the cheap essay writing service, there are good suggestions.
 

OldUncle

New member
Joined
Mar 10, 2019
Location
Tbilisi, Georgia
TDI
1999 Golf mk4 hatchback / 1998 Golf mk3 Variant
Hi there!

Finally I got the ability to post!

I am twice TDI owner (Passat&golf).

Going to invest in Jetta 2000 TDI 90 HP.

Fuel economy is my question. The information I found on internet is different on different websites.

So, from the practice: what is the fuel economy of the above mentioned model?

I apologise, in advance, if I appear on the wrong thread.





Sent from my Moto Z2 Play using Tapatalk
 

OldUncle

New member
Joined
Mar 10, 2019
Location
Tbilisi, Georgia
TDI
1999 Golf mk4 hatchback / 1998 Golf mk3 Variant

Jetta_Pilot

Top Post Dawg
Joined
Apr 14, 2005
Location
West Hill, Ont. Nov.2nd in Mexico till April 27th
TDI
2015 Passat Highline TDI Candy White (SEL Premium) long gone 2002 Jetta TDI
Regardless of anything, the only way to improve Mpg is to slow down, no jackrabbit starts and slowing down well before getting to a red traffic light. This is a proven fact, not my opinion!

Those in these forums who claim to drive 85Mph and get 70Mpg must be smoking something really good!
 

ranger pete

Veteran Member
Joined
Jul 29, 2011
Location
connecticut
TDI
2011 JSW 6MT
I have about 3K on my "new" '11 JSW MT. I've gotten between 43-45 mpg so far. I do drive it for mileage, but I don't drive it slow. Plenty of 65-75 highway. I also occasionally do a bit of turbo vane cleaning with 3-4th gear pulls to 4.5K revs.
 

Mike14VW

Member
Joined
Jun 13, 2019
Location
Wilpo
TDI
2014
Just wanted to add I've been averaging 43-44 mpg since I bought my 2014 jetta TDI. I decided to take my car in for service and have the fuel filter changed seeing as the car had sat for almost a year after VW bought back. The second fuel up after having filter changed (which averaged my mpg from the prior fill up) I gained 3 mpg's. I am now consistently averaging 47-48 mpg's. My 5houghts are the car sat and the filter may have taken on moisture with mold growing causing the filter pores to clog. Which in turn yielded the car to pull more fuel.

Will continue to monitor, but so far I've had four fill ups since having filter changed and all have yielded 47+. Also had my coolant system flushed but dont thjnk this would caused any increase.

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CheapBastard

Veteran Member
Joined
Jun 12, 2019
Location
California
TDI
2014 JSW
Just wanted to add I've been averaging 43-44 mpg since I bought my 2014 jetta TDI. I decided to take my car in for service and have the fuel filter changed seeing as the car had sat for almost a year after VW bought back. The second fuel up after having filter changed (which averaged my mpg from the prior fill up) I gained 3 mpg's. I am now consistently averaging 47-48 mpg's. My 5houghts are the car sat and the filter may have taken on moisture with mold growing causing the filter pores to clog. Which in turn yielded the car to pull more fuel.

Will continue to monitor, but so far I've had four fill ups since having filter changed and all have yielded 47+. Also had my coolant system flushed but dont thjnk this would caused any increase. I’d be stoked to get 43/45

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Yeah I just bought one that’s been sitting for a couple years too, only has 15k on it but I’m changing it out next week
 

Mike14VW

Member
Joined
Jun 13, 2019
Location
Wilpo
TDI
2014
Damn that's low mileage. Idk why VW isent proactive about changing the filter. Not really a safety issue though.

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Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
I don't know why the buyers aren't proactive in asking that these kinds of things be done pre delivery. I bought my car new as a stop sale car, but I requested all fluids filters and full servicing be done before I took possession. If you are buying one of these cars I would insist on a full servicing before taking delivery, or no sale. If the price is too good to pass up then pay for the service yourself. To do neither of these choices and complain later is just folly. VW is not going to be proactive on any of these cars as they just want to get rid of them at this point with as little cost as they can get away with. If it costs them too much they just go to the crusher and they are done with them. In some respects I bet they wish they would all just go away and relieve them of a very long continuing headache.
 

Mike14VW

Member
Joined
Jun 13, 2019
Location
Wilpo
TDI
2014
Lightflyer, I would agree. I negotiated on the side of I would be doing it. All vehicles I've bought I've always gone through and changed all the fluids and filters knowing (in my opinion) that majority of car owners do not do service past motor oil and filter changes. I also changed my gear oil.

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