New diesel question

cowboyracer43 · #1 09/10/06, 05:45 PM

In 1998 I bought my "last new car," a '98 VW "new beetle" diesel TDI. Throughout its first 250000 miles I delighted in its speed and efficiency. I was pleased with 46-50 mpg and its occasional 700 miles on a tank of fuel. In the last month, I have noticed a drop in mpg and thought "it must be the wind" or "I need a tuneup." Yesterday I drove to NE Colo to watch DD play in a volleyball tournament. I needed to fuel up before I had driven even 500 miles. I have been seeing notices on diesel pumps about a low sulfur diesel reformulation. I have also learned that VW will not be making a 2007 (American bound) diesel because of the reformulated low sulfur diesel gas required in the US. The "no 2007 VW" policy is merely a "suspension" while VW re-designs its engine to make it compatible with US fuels. My question: Is my 20% decrease in mileage attributable to the reformulated low sulfur diesel fuel? Can the old diesel still be obtained for "the old" diesel vehicles? Finally was I premature in buying my "last new car?"

MWG · #2 09/10/06, 05:49 PM

No, old diesel can not be purchased. However, you can use the new diesel in old vehicles.

MWG · #3 09/10/06, 05:50 PM

Quote:

Originally Posted by cowboyracer43

My question: Is my 20% decrease in mileage attributable to the reformulated low sulfur diesel fuel? Can the old diesel still be obtained for "the old" diesel vehicles? Finally was I premature in buying my "last new car?"

Where did you get this 20% figure?

mightybooboo · #4 09/10/06, 05:52 PM

These folks would be a good bet to find the answers you seek.

http://forums.vwvortex.com/zeroforum?id=22

BooBoo

Hammer4 · #5 09/10/06, 05:53 PM

You more than likely have a clogged intake manifold ... the egr valve on the vw diesels can pass enough oil fog to clog the intake in some conditions ( primarily if you really are easy on the accelerator )...

Try www.tdiclub.com for more info, I don't think the fuel has anything to do with it.

mtman · #6 09/10/06, 06:24 PM

hey new people try putting your question in the right forum this belongs in shop talk

Macybaby · #7 09/10/06, 07:35 PM

Hubby's guess would be dirty fuel and/or air filter. You may have two fuel filters, so make sure to change both. Also, has it started smoking more - indicates a dirty injector.

He said it's very unlikely it has anything do to with the new fuel.

Cathy

MWG · #8 09/10/06, 07:42 PM

As I reread your post I understand now... no, it is not the new fuel. There is almost no difference in fuel mileage, only cost. There is something else going on with your car.

fordy · #9 09/10/06, 08:25 PM

Quote:

Originally Posted by cowboyracer43

In 1998 I bought my "last new car," a '98 VW "new beetle" diesel TDI. Throughout its first 250000 miles I delighted in its speed and efficiency. I was pleased with 46-50 mpg and its occasional 700 miles on a tank of fuel. In the last month, I have noticed a drop in mpg and thought "it must be the wind" or "I need a tuneup." Yesterday I drove to NE Colo to watch DD play in a volleyball tournament. I needed to fuel up before I had driven even 500 miles. I have been seeing notices on diesel pumps about a low sulfur diesel reformulation. I have also learned that VW will not be making a 2007 (American bound) diesel because of the reformulated low sulfur diesel gas required in the US. The "no 2007 VW" policy is merely a "suspension" while VW re-designs its engine to make it compatible with US fuels. My question: Is my 20% decrease in mileage attributable to the reformulated low sulfur diesel fuel? Can the old diesel still be obtained for "the old" diesel vehicles? Finally was I premature in buying my "last new car?"

.............................The current low sulphur diesel is just an intermediate step which will go even lower down to 15ppm beginning on Jan.1 , '07 .
This "new" fuel has LESS energy per combustion cycle than the old 500 ppm we are currently using . It can't help but result in Lower fuel milage but the refiners are supposed to be adding additional "lubricity" agents to compensate for the reduction in sulphur . Both diesel locomotives and jet engines will be exempted from the lower standards and will continue to beable to pollute the atmosphere bless their little hearts . Can't have the Big birds with the Brass Ass' falling out of the Sky now can we !!! fordy...

fantasymaker · #10 09/10/06, 08:57 PM

[QUOTE=fordy]....
This "new" fuel has LESS energy per combustion cycle than the old 500 ppm we are currently using . QUOTE]

HUH? wheres this from? I thought it had less SULFER since I work in this field Id thought Id have heard about it. the supposed reason the new engines are getting less milages is that supposed to be cleaner

fordy · #11 09/10/06, 09:27 PM

[QUOTE=fantasy69maker]

Quote:

Originally Posted by fordy

....
This "new" fuel has LESS energy per combustion cycle than the old 500 ppm we are currently using . QUOTE]

HUH? wheres this from? I thought it had less SULFER since I work in this field Id thought Id have heard about it. the supposed reason the new engines are getting less milages is that supposed to be cleaner

............ http://www.chevron.com/products/prod...sel/ulsd.shtml
............go to #12 and peruse "energy content" . fordy...

halfpint · #12 09/11/06, 02:42 PM

The mileage on our VW TDI went way down (to about 35 mpg) recently, and we found the fuel filter was leaking. Put a new one on and mileage went right back up, so you might want to check that out.
Dawn