Newbies and Vets: Tips for better fuel economy!

[boutmuet]

For Chevron stations, make sure the pump is labeled "Techron-D". I must live on the edge between two distributors. I can't imagine how that's possible, but one of the smaller Chevron stations here hasn't gotten the new formulation yet.

I believe they only sell techron D in Sacramento and nearby. I'm not sure if they have a higher cetane I think it is just the additive they have in the fuel.

 

[abbeyinc]

I would be interested to know what Tesoro and Carr's/Safeway Stores values are. How do I go about figuring that out? There seems to be a 5mpg difference between the brands in my B4.

 

[NarfBLAST]

How do I go about figuring that out?

Start with their web site if they have one and see if it is posted, if not then find an email address for customer inquiries and send them an email. If they reply post the information here but do not include personal details of the person who emailed you (like last names, their email address, their direct phone number).

 

[Harden]

Does coasting in Neutral with the 6 spd auto in the 09 Jetta hurt the trans w/ the eng running? I find my MPG goes way up when I shift into neutral and use the car's momentum to coast up to the next light or into a parking spot.

I believe from what I've read, you can get even better MPG if you coast in the highest gear you can keeping the RPM over 1200. The transmission is turning the engine, and not the use of fuel (fuel is not being supplied to the engine during this type of coasting). When you coast in neutral, your still using some fuel to keep the engine going.

Please someone correct me if I'm wrong.

 

[97pssat04golfTDIs]

I believe from what I've read, you can get even better MPG if you coast in the highest gear you can keeping the RPM over 1200. The transmission is turning the engine, and not the use of fuel (fuel is not being supplied to the engine during this type of coasting). When you coast in neutral, your still using some fuel to keep the engine going.

Please someone correct me if I'm wrong.

You are correct, but there are certain situations where one coasting in neutral is better than coasting in gear. I have series of hills that I can coast over in neutral but if I put it in gear the engine braking slows me down enough so it negates any mpg gain when I have to step on the fuel to get over the rest of the hill. When approaching a stop using down shifting to slow down some instead of just brakes helps also. This subject can inspire some crazy debates IMHO both are good techniques that have specific situational applications. My $.02 on the subject.

Take care,

 

[NarfBLAST]

I can coast in neutral much farther than I can coast in gear and using a Scangauge I have found that average trip fuel economy is usually better if I coast in neutral especially at higher speeds because I can conserve much more momentum. I coast in gear only when I need to slow down. Diesels use very little fuel at idle.

I'm currently getting my personal best tank fuel economy averages ever by concentrating on the "conserve momentum" philosophy. This involves leaving ludicrous ammounts of space between my vehicle and the vehicle in front of me when cruising on the highway, coasting in neutral on most down hills, slowing down and trying not to stop for red traffic lights (ie slow early in order to not arrive at light before it turns green). I actually love slow congested traffic now because I get my best fuel economy numbers when the highway slows from 100km/h to 80km/h or even 60km/h average speed, I just leave lots of space and avoid using the brakes and I watch my trip average fuel consumption drop on the Scangauge.

 

[OldMan52]

I can coast in neutral much farther than I can coast in gear and using a Scangauge I have found that average trip fuel economy is usually better if I coast in neutral especially at higher speeds because I can conserve much more momentum. I coast in gear only when I need to slow down. Diesels use very little fuel at idle.

I'm currently getting my personal best tank fuel economy averages ever by concentrating on the "conserve momentum" philosophy. This involves leaving ludicrous ammounts of space between my vehicle and the vehicle in front of me when cruising on the highway, coasting in neutral on most down hills, slowing down and trying not to stop for red traffic lights (ie slow early in order to not arrive at light before it turns green). I actually love slow congested traffic now because I get my best fuel economy numbers when the highway slows from 100km/h to 80km/h or even 60km/h average speed, I just leave lots of space and avoid using the brakes and I watch my trip average fuel consumption drop on the Scangauge.

100% agree NarfBLAST. A few people rely on hybrid technology to conserve momentum, but much of this can be done, without electric motors and batteries, by driving sensibly. In the beginning, it may seem like a lot of things to concentrate on, but soon it becomes a natural way of driving.

I seldom do a full stop (hope no cops are viewing!). I slow down nearly to a stop, and I then accelerate starting in 2nd gear. Even when I do a good amount of city driving, I don't see a significant difference in MPG.

Conserve momentum is the way to go.

 

[jimlockey]

With all these 100+ days my car is very busy trying to keep me cool.

 

[Tom Servo]

This involves leaving ludicrous ammounts of space between my vehicle and the vehicle in front of me when cruising on the highway, coasting in neutral on most down hills, slowing down and trying not to stop for red traffic lights (ie slow early in order to not arrive at light before it turns green).

Canadian drivers must be more polite than American drivers. Even here in rural Mississippi I get tailgated and passed if I leave more than a car length in front of me on these two lane roads.

I think that we as a continent could save soooo much more fuel if our governments would merely re-time or upgrade their stoplights. This state has to be the WORST for having the old-fashioned timed lights, with no trip sensors, or with sensors deactivated. Depending on the cycle, I can lose a good 10 minutes waiting for no one in the middle of the night in my town that's just a few miles long. Down the road a piece is a four-lane US highway, and where it intersects a state highway miles and miles from civilization is a nice shiny new LED stoplight system. It keeps the four lane major US highway on red for two minutes, with a 12 second green, 24 hours a day. It has to be the most asinine setup in the world, because the state highway probably carries 1,500 cars a day, versus the 7-10,000 on the US highway. All those people stopping from 65-70 mph, then accelerating back up. What a waste. Planning for momentum at that intersection is a real PITA!

 

[ebolamonkey]

If someone would just come out with a diesel electric hybrid!!!

http://www.treehugger.com/files/2008/02/volkswagen_to_i.php
Here is your 70mpg VW.

BTW, Chevron left the South East region. The only stations I see with Diesel fuel are:

BP
Shell
Love's
Raceway

 

[Tom Servo]

BTW, Chevron left the South East region. The only stations I see with Diesel fuel are:

BP
Shell
Love's
Raceway

When did that happen? Last time I was in Birmingham I saw several Chevrons with diesel, and the one up the road from me in Batesville, MS also offers diesel.

 

[bockegg]

I'm having trouble finding the right post for this question. Is it possible to "vent" the '09's? This would help your miles per tank if you could. Loved doing that in my '06.

 

[velociT]

I'm having trouble finding the right post for this question. Is it possible to "vent" the '09's? This would help your miles per tank if you could. Loved doing that in my '06.

no vent to remove.

The Mk5-A5 section is the appropriate forum.

 

[No1uknow]

Fuel Economy

You guys have posted some great tips. I drive from Virginia to New York every other week and sometimes every weekend. My car is a 2005 TDI Golf. Everything is stock, no aftermarket anything. I regularly get 60 - 62MPG. They key is to use a good grade fuel, as many guys have mentioned here in the thread. I use Schaffer Diesel Treat as an additive. It is a little pricey but works better than ANY competitor on the market in improving mileage - I've tried them all. I order the stuff 4 gallons at a time (everything I own is diesel). Four gallons have lasted me since I bought the car new in 05 - I have two gallons left. Currently the golf sees 4,000 miles per month and is the most fuel efficient machine on the highway - hands-down. Another key is a clean air filter. As mentioned in this thread, don't waste your time with aftermarket cold air intakes unless you are into racing. Most folks purchase a TDI for performance and economy and reliability all with a balance. The TDI is a well overbuilt engine and can be retro fitted with components that will make it burn the tires off. But expect to reduce component half-life by pushing the limits. Personally I use Shell Rotella T 5W-40 in my engine and I change it every 10K miles religiously. I do drive pretty hard, not reckless. I can drive 80 Miles per hour and still achieve 55-58MPG. The worst mileage I ever got was when the car was new. Then I got about 43-45 MPG. The second worst was carrying over 1000 pounds to NY. Then I got around 49MPG.

Again speaking of fuel, my TDI will sense bad fuel almost immediately and I notice it immediately due to lack of power. I have purchased fuel at an East Coast and at a Loves and got bad fuel. Pull onto the interstate and immediately feel a slight engine shutter upon a call for more fuel under load. Almost feels like a stopped up fuel filter. Their fuel sometimes is good and sometimes is bad. Never got water in the separator though, ever. I keep fuel additive in NY and VA because of this.

But in summary, keep the car's fluids fresh, keep clean air filters on the engine (a diesel's life-blood is air), only use high grade fuel, shift sensibly (don't short shift - but don't overspeed the engine by shifting at 4000RPM either), and use cruise control on long hauls (despite the myths on various threads, cruise control will help fuel economy as the computer can regulate throttle a lot more efficiently than the driver can). Let the engine idle rather than shutting it down for short stops (be vigilent though and don't leave the car unlocked running at the fill-up station - you can lock the door with the engine running utilizing the second key, without the immobilizer shutting you down). But maintain situational awareness and pay close attention to the car or risk it jacked, even if locked. Stopping and restarting a diesel for short stops makes no sense as they burn trivial amounts of fuel at idle. More wear is placed on the engine at startup than at any other time - let it idle if at all possible (trust me, there is no global warming and you are not contributing to it by allowing your car to idle for an extended period of time).

The TDI engine is a remarkable power-plant. I have owned many cars and trucks through the years but none as well balanced and reliable (stock) as the TDI. And it is a proven engine and technology. Who could ask for anything more. And believe me, a hybrid anything doesn't come close to the TDI in performance, reliability and mileage combined.

Remember this final thought - if your car is stock AND you see excessive black smoke on strong accelerations (soot-ball levels of smoke) - suspect that the air filter needs replacing and believe it or not, the fuel filter! KEEP both filters clean and drive the car sensibly and the filters will quickly pay for themselves in returned fuel mileage, especially on long hauls. My TDI's mileage is phenomenal... good luck on yours!!!

 

[boutmuet]

Anyone happen to know the cetane levels for 76/Conoco/Phillips stations? Their website is extremely vague.

 

[OldMan52]

Remember this final thought - if your car is stock AND you see excessive black smoke on strong accelerations (soot-ball levels of smoke) - suspect that the air filter needs replacing and believe it or not, the fuel filter! KEEP both filters clean and drive the car sensibly and the filters will quickly pay for themselves in returned fuel mileage, especially on long hauls. My TDI's mileage is phenomenal... good luck on yours!!!

Very good narrative No1uknow. And I used to constantly check exhaust smoke thru my reer-view mirror to make sure I was driving my 2001 NB properly. But now I have a 2009, and you don't see any more smoke. The filter traps it all, so you don't see if you're doing OK anymore. Good thing I've been driving diesels for 25 years, but new diesel drivers may need tips like the ones you're giving to learn how to drive a diesel.

I appreciate your suggestions.

 

[wagonater]

Fuel

Got a 05 Passat Wagon 2 lt TDI all stock from Canada...im only getting 800 - 900 kms per tank. What the heck am I doing wrong.

 

[BleachedBora]

If you're filling up until the pump shuts off you have 6-8L of foam/air in the tank. That along with:
a) It's a heavy, large Passat
b) It's an automatic
c) Is your fuel filter clogged? Bad Fuel? Low tire pressure? City/highway driving. How hard you accelerate, it all adds up...
-BB

 

[wagonater]

thanks..have nitrogen air in tires, i do do a lot of highway driving. My next oil chnage, the fuel filter will be changed not sure when it was last done...just got the car in april so we are still feeling her out. thanks again..see you in September

 

[1CleanTDI]

I replaced the air filter and did an oil change last weekend. Immediately I could tell the mileage was better (went unusually far on 1/2 tank). After filling up my guess is I picked up around 4mpg.

 

[JettaJake]

"guess"?! Come on, you can do better than guess.

 

[boutmuet]

Just to be sure BP/Amoco is NOT the same as ARCO in the west in terms of cetane?

 

[BleachedBora]

Yes, as far as I know--saw some news reports on the quality of their gas, if it's anything close to that with diesel then I wouldn't trust my car to come within a mile of an ARCO station!

 

[Lokhankin]

Pardon my ignorance, but reading through these 24 fine pages I still could not find a good methodology on how to address hill climbing.
Most of discussion is about coasting downhill and few about accelerating downhill in order to take it easy uphill.
I'm looking at these and possibly other variations on how to achieve the best MPG during:
1) Hwy. Straight - 60 mpg. Facing long uphill:
- 0.5-1 miles - 10-15% incline;
- 0.5-1 miles - 20-25% incline;
2) Hwy. Downhill - 60 mph. Facing long uphill:
- 0.5-1 miles - 10-15% incline;
- 0.5-1 miles - 20-25% incline;
3) Entering Hwy. Facing long uphill:
- 0.5-1 miles - 10-15% incline;
- 0.5-1 miles - 20-25% incline;
4) Local road (40mph speed limit). Facing long uphill
- while moving on straight road;
- or from a stop.

Any takers?

 

[JoeSixPack]

Rear Spoiler and Timing

Hey folks - new to the forum here and new to the the TDI world (though had an old non-turbo '83 Jetta Diesel that I drove for a few years back in the 90s.)

Just picked up a 2000 Jetta GLS TDI wtih 170,000 miles on it

Among other improvements I had the timing belt/water pump replaced. Before it was replaced the timing was off slightly but it was still getting 49 mpg on the highway.

Now that the belt's replaced the timing has been set exactly to the factory specification and the MPG has dropped to 43. I understand that having the timing set to the factory specs is better for the engine in the long term but does result in the lower mpg. Since I'm not expecting to get 400,000 miles out of the body, I'm inclined to have the timing adjusted for better MPG in the short term.

Any thoughts on this as a trade off? Am I doing any significant harm to the engine?

Also, at one point the Jetta had a rear spoiler (the holes are filled but still apparent.) I'm considering putting a spoiler back on for aestetics but heard that the additional drag it creates can also reduce MPG.

Does anyone have any real world experience with MPG with a spoiler on compared to off?

Thanks! Great forum... already picked up a lot here.

 

[owner]

I just asked for cetane levels at Sheetz, and here is the response:

Our Ultra Low Sulfur Diesel has a minimum cetane rating of 40. Additional details attached.
· SPECIFICATIONS FOR FUNGIBLE ULTRA LOW SULFUR DIESEL ( ON ROAD )
· GRADE 190 (EPA DESIGNATION: DMV2D015)
· ASTM TEST TEST RESULTS
· PRODUCT PROPERTY METHODS MINIMUM
· Cetane Number D613, D6890 40
· Cetane Index D4737 40

 

[owner]

does anyone know cetane levels at Kwik Fill? I tried getting a hold of them but unfortunetly have received no response.

 

[rotarykid]

Flying J in Wytheville VA has the pumps marked 45 minimum cetane . From what I know this is a common rating for D2 pumps in colder climates like western mountain VA . Higher cetane makes the engine run smoother and for an easier starts in the morning when it's really cold . But a couple of points of cetane really makes little difference in mpgs .

 

[BleachedBora]

Most cheap places guys are going to have 40-42. Also known as "rot-gut" fuel. Minimum cetane in north America is 40, so if they have that listed then it's the bare minimum that they can get from the refinery with no additives at all. (Remember your car is designed to run on minimum 49 cetane). This is why it has been recommended to go to more established stations with higher cetane levels. Your fuel injection system will thank you for the service....
-BB

PS Thanks Owner, I'll add that to my list on the first page!

 

[boutmuet]

Would the cetane numbers be any different at a Chevron than is selling #2 significantly less than other Chev's in the area?

For example a Chevron has #2 for $2.85 while just a few blocks away another Chevron is selling #2 for $3.09