Newbies and Vets: Tips for better fuel economy!

[JettaJake]

question on mpg

have been reading and apprecaite info got a 2002 tdi get decent mileage
since i purchased car 2 years ago plastic under engine broke off snow and ice

was wondering would this affect mpg at all since it creates some type of change in air under car

thank you in advance

The mileage effect is not large but read up/search on "skidplate" -- evolution and dieselgeek supply aftermarket metal skidplates and there is an OEM version, too. Get something that will protect your aluminum crankcase (which the OEM plastic piece never did) -- $$ well invested.

 

[intern]

thanks for info jetta jake

 

[Honeydew]

question on mpg

have been reading and apprecaite info got a 2002 tdi get decent mileage
since i purchased car 2 years ago plastic under engine broke off snow and ice

was wondering would this affect mpg at all since it creates some type of change in air under car

thank you in advance

Also consider how much more of that wet salt from your winter roads will make its way into the engine bay without the plastic cover or a skidplate in place. The turbo actuator, for example, is rather susceptible to corrosion and when it stops cycling properly MPG will certainly drop. Mine did.

 

[dieselmike]

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.

 

[dieselmike]

Any Cetane #s for Murphy's station (walmart), HEB station, Texaco, or Conoco filling stations?

 

[IN-TDI]

CountryMark Coop Diesel - cetane 50+

Here is a response to an email of why I was getting lower mileage with winter fuel. BTW, all of CountryMark's diesel is produced from Illinois Basin oil. Othewise a cetane of 50 will be great when it warms up.


"The cetane of the Premium Diesel-R / B5 you are purchasing at the CountryMark station in central Indiana is a miniumum of 50. However cetane plays a small part for fuel economy. The fuel is seasonally blended in the winter months with kerosene to prevent gelling that causes filter plugging. Kerosene is a "lighter" fuel and though it improves cold weather operability it contains less BTUs per gallon than the Premium Diesel-R / B5 which will decrease the fuel economy.

It is typical for a truck stop on the interstate not to blend their fuel in the winter because the vehicles filling there are already running and the circulation of the fuel back to the vehicle tank keeps the fuel warm and prevents gelling. Stations located off the interstate are generally dealing with customers such as home based fleets where cold weather starting is a concern."

 

[06JettaGuy]

Just learned that the cetane coming out of Port Arthur Refinery is at 54.5. That is for the current ULSD leaving the refinery. Trying to get copy of COA for verification. Way to go Shell... The lab analysis shows just above 51 for the cetane... this is really awsome to know!!!

 

[newbury]

Just learned that the cetane coming out of Port Arthur Refinery is at 54.5. That is for the current ULSD leaving the refinery. Trying to get copy of COA for verification. Way to go Shell... The lab analysis shows just above 51 for the cetane... this is really awsome to know!!!

Aw, it's probably not worth it to drive to Texas from DC JUST for a high cetane!

But then again the JSW isn't broken in yet!

 

[06JettaGuy]

Aw, it's probably not worth it to drive to Texas from DC JUST for a high cetane!

But then again the JSW isn't broken in yet!

Just to make your day a little better... the Cetane for ULSD coming out of LA refineries at New Orleans is 48... That product travels up the Colonial pipeline all the way to Baltimore.... Shell/Motiva has terminals in Fairfax and Springfield... Those cover all of DC.... with a little bit of Power Service you are looking at about 54 cetane.... How are those numbers!! Hit those Shell Stations!!

 

[GgOTi]

Does anyone happen to know what cetane Exxon/Mobil stations usually have? I am in the Orlando area for school and see quite a few of them offering diesel.

 

[ruking]

You're probably right, it's the BP/Amoco stations that had the 51 rating. We have standard BP in the northwest as well and I heard that it's lower quality.

Northern California has Chevron with Techron D, which makes them have a cetane of 50ish. Good stuff .

Thanks for the heads up for the Northern CA information. It sounds like 1. Chevron, 2. Shell are the ones with the highest Cetane ratings. I have a USA station a mile from the house and it is often the cheapest in the area. It swaps price positions with Valero as the alternate. Occasionally the Shell and Chevron get real competitive, and I act accordingly! I do use either Primrose 405C or Power Service, so even the lesser cetane products get a theortical boost. It is truly hard to tell if it makes a difference in the scheme of things.

 

[Baumeister]

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.

 

[ruking]

Well the Chevron station I would use is .25 miles from the 25-50 mile radius distribution point.

 

[BleachedBora]

True, the Techron D is awesome stuff; but from what I know standard Chevron diesel is still at least 49. I just got 51.25 MPG driving 70-75 on winter fuel with the stuff ('98 Jetta TDI). Driving back to Portland I still got 49 and I was doing 80-85 the whole way. Same car in the past would get 43-44 on Flying J .
-BB

 

[nokivasara]

The Diesel sold in Sweden has a cetane rating of 57 (preem) and 52 (OKQ8)

Still the mileage is about the same everywhere in the world, strange isn´t it?

 

[BleachedBora]

How long does the fuel system (injection pumps etc...) last though? Probably longer than they do here. Also, minimum cetane in the US is 40. Minimum in Europe is 46. We have 40-51ish, doesn't surprise me that you have 46-57ish. Going above 49 doesn't get you much benefit as the cars were designed for 49. Going under 49 though and you start to see differences...

Vasara? That's hammer på Finska.
Nähdään,
-BB

 

[nokivasara]

How long does the fuel system (injection pumps etc...) last though? Probably longer than they do here. Also, minimum cetane in the US is 40. Minimum in Europe is 46. We have 40-51ish, doesn't surprise me that you have 46-57ish. Going above 49 doesn't get you much benefit as the cars were designed for 49. Going under 49 though and you start to see differences...

Vasara? That's hammer på Finska.
Nähdään,
-BB

Yeah I don´t actually have a clue of what a higher cetane rating means, I just noticed that you have much lower rating than we do. Minimum in Sweden is 50.

Vasara is indeed hammer, and Noki is soot = soothammer (nokivasara is a common name for a diesel powered car at least in northern Finland where my dad comes from)

 

[SimBG]

Hi, I'm newb but I haven't read that tip anywhere.
When you're driving on highway with a truck in front of you, follow it closely (at safe distance). The reduced drag results in a great MPG increase.
Agreed, it won't give you 60MPG but it's still a great time saving/good mpg trick.

 

[BleachedBora]

Yeah I don´t actually have a clue of what a higher cetane rating means, I just noticed that you have much lower rating than we do. Minimum in Sweden is 50.

Vasara is indeed hammer, and Noki is soot = soothammer (nokivasara is a common name for a diesel powered car at least in northern Finland where my dad comes from)

Vai niin, en tiennyt mitä noki tarkoittaa. Hyvä sana! Asuin Suomessa väin kahdeksi vuodeksi. Olen menossa takaisin Ruotsin ja Suomeen kesällä.
Heippa,
-BB

 

[DaMidget]

Hi, I'm newb but I haven't read that tip anywhere.
When you're driving on highway with a truck in front of you, follow it closely (at safe distance). The reduced drag results in a great MPG increase.
Agreed, it won't give you 60MPG but it's still a great time saving/good mpg trick.

I believe that MythBusters did this once, they determined you would have to be within a couple feet to actually see any gain -- far to close to be considered a safe distance.

Anyone else remember that episode?

 

[NarfBLAST]

I believe that MythBusters did this once, they determined you would have to be within a couple feet to actually see any gain -- far to close to be considered a safe distance.

Anyone else remember that episode?

I saw that episode and you seem to remember it completely wrong!

They found gains anywhere behind the big truck... the gains got better and better until they got within a few feet at which point the gains dropped off because they were feathering the accelerator too much. This leads in to the best way to conserve fuel on the highway which can be found if you click on "anti-traffic" in my signature.

 

[DaMidget]

I saw that episode and you seem to remember it completely wrong!

They found gains anywhere behind the big truck... the gains got better and better until they got within a few feet at which point the gains dropped off because they were feathering the accelerator too much. This leads in to the best way to conserve fuel on the highway which can be found if you click on "anti-traffic" in my signature.

Well I'll be: http://kwc.org/mythbusters/2007/06/episode_80_big_rig_myths.html

• 5mph control: 32mpg
• 100ft: 35.5mpg, 11% improvement
• 50ft: 38.5mpg, 20%
• 20ft: 40.5mpg, 27%
• 10ft: 44.5mpg, 39%
• 2ft: 41mpg, 29%

 

[Turbospool]

...... the best way to conserve fuel is probably the best way to spend money on front end repairs plus blah blah blah. I simply cannot figuire out who would enjoy their ride with the rear end of a semi in their face for any worthwhile amount of time, ...... saying nothing of how much any semi driver will appreciate anyone hanging onto his tail .......

 

[daniel_mad]

i just got a performance chip, however, now it seems my fuel economy has suffered. Any idea why and what i can do to fix it?

 

[Bob_Fout]

Have you been enjoying the new power much?

 

[Tom Servo]

i just got a performance chip, however, now it seems my fuel economy has suffered. Any idea why and what i can do to fix it?

Stop enjoying the new power?

 

[moonranch]

Hello, I am new to TDIs, but have been driving diesel pickups for years. I would say one of the important things for increasing your MPGs is how you drive. One of the "add-ons" on my truck shows current throttle position and engine load. Using these along with EGT, I learned when to shift and how to drive the the truck for best economy. Speed is a big factor on my truck, I get better economy on my commute than I do on the interstate. My commute is 35miles(one-way) going from 7500ft to 5100ft elevation, most of it is rural 40-50mph roads, with 4 or 5 stop lights once I get into the city. Obviously, with a truck economy is more variable depending on load. I have been as low as 15mpg heavy towing on the highway, and have seen several fill-ups between 26-28mpg(with 150K on the stock Michelins) on my commute. Thanks for all the info, I did not know about the 49cetane requirement.

 

[Sevenjays]

Whoa, that was a lot of reading! But I think I got some good info. Now I have to figure out if it's worth driving 10 miles out of my way for Tecron D at the Chevron station. I have a flat commute mostly on 4 lane highway and I'm going to try to slow it up a bit and see what happens. Right now we are doing 37mpg. Mostly highway. I commute 75 miles rt Sat through Monday, my wife does about the same trip Tues through Sat. I don't know if I can convince her to slow down though. If I see some improvements, I'll post them.

Thanks to all, especially for making my 12 hour night shift go by quicker with all the humerous if not enlightening posts/rants!

DJ

 

[Mike_M]

9) Larger turbo--again better breathing leads to better economy. Hybrid turbos appear to do the best for economy. ($850-3,000+)

Really? Granted, I haven't been around in a while, but everything I read here previously told me the opposite, that a bigger turbo would cost MPGs in creating back-pressure in low-load situations, and taking more effort to spin up a heavier turbine. (At least, I think that was the explanation IIRC.)

Wow. That just put "bigger turbo" back on the table as a viable option after 4 years of me thinking that was the one thing I wouldn't touch.

And it won't be on the Jetta in my sig. I have a beautiful, white 2-door surprise coming home with me after I fly to where it is next weekend and pick it up.

 

[tasdrouille]

The only way to tell would be with EMP measurements. If both turbos are pushing the same MAP, is the EMP lower with the bigger turbo? I somehow doubt it.

One way to reduce backpressure, and increase fuel economy, is to change the boost map so less boost is applied at low loads. That's often done on diesel pickups with vgt turbos.

There's no big gain to be had there, especially not for the price, but stellar fuel economy is the sum of countless little things.