My daily drivers are notoriously inconvenient. The motorcycles scare away most passengers while my cars are both two-seaters (one is a three-seater and, no, it isn't a McLaren F1) - none of these can comfortably travel 200 miles without hitting bingo fuel. So, as I pondered my escape from L.A. to a quiet little cabin in the woods, the opportunity to take a long-termer presented itself - our plug-less Jetta that runs on biodiesel.
But wait...will it get me from Santa Monica to the San Bernardino mountain range and back with various errands, on a single tank? I'm guessing 300 miles at least, allowing a bit more fuel for holiday traffic. I hope so, because I'm not finding any B99 fuel pumps anywhere near my destination.
My co-workers assured me that I'd have nothing to worry about - one mentioned that 400 miles on a tank would be easily within my grasp. But being the new guy on staff, I was still filled with doubt. Chalk it up to a few years of driving vehicles with limited fuel capacities or horrible gas mileage. I set off on my weekend getaway expecting to limp back to L.A. running on soy-based fumes, or worse, having to fill-up on regular diesel, breaking the biodiesel fill-up chain.
About 80 miles outside of L.A. the fuel needle has barely moved. OK, I'm already impressed. Then I started the climb into the mountains, with windy roads and steep grades that induce that diesel rattle. By the time I climbed to the 6,000 foot elevation mark, the needle made a dive of about a quarter tank. Uh-oh. Thinner air and aggressive driving don't agree with fuel economy.
Running more errands to buy the things I forgot to pack (why must I always forget the marshmallows?) and an excursion into neighboring Big Bear made me feel as though I was tempting fate. By the time I settled in, I was almost at a half-tank, but I also knew the drive home was downhill.
I was expecting a traffic mess on the way back to L.A., but it was smooth sailing all the way in. The Jetta tackled the downhill curves with ease, albeit with quite a bit of tire howl. I returned home with over 3/8ths of a tank and 290 miles on the clock, effortlessly averaging 36.7 mpg at highway-plus speeds. My trip ended-up much like the Jetta itself - uneventful, drama-free and bordering on boring.
Mark Takahashi, Associate Editor @ 61,072 miles
greenpony says:
04:14 PM, 09/ 2/08
Nice picture. You guys in California get beautiful scenery.
Respectable gas mileage. I would have expected a little higher (40+) since this was mostly highway, but I imagine climbing hills may have affected that. Has there been a difference in fuel economy since switching to B99 (versus pure diesel)?
My Focus has actually averaged the exact same 36.7 mpg over the last three tanks. I think where the Jetta has it beat is in maximum economy... I'm sure the Jetta should have no problem exceeding 45 mpg (maybe 50?) whereas I've yet to beat 39 mpg in the Focus (2007 ZX4 MT 2.0L if you're curious).
One last thing. I thought thinner air was supposed to increase fuel economy, not hurt it, since the ECU compensates for less air with less fuel. (?)
cah11705 says:
04:23 PM, 09/ 2/08
Just outta curiousity, what are your other cars?
felonious says:
04:37 PM, 09/ 2/08
^^^ Yeah I wanna know too!
mtakahashi says:
04:54 PM, 09/ 2/08
greenpony: Phil Reed managed to barely break 50mph on his drive (4 posts back for this car). I think I could do that with a little more patience and self-control, but where's the fun in that? Altitude affects the efficiency of engines because of the loss of air density - much like how I was huffing and puffing after a 30 min. hike up there! Plus I was kinda pushing the Jetta hard in the passing lanes.
mtakahashi says:
04:55 PM, 09/ 2/08
My daily drivers are split-up between a Honda sportbike, Harley cruiser, Lotus Elise and 1957 Thunderbird.
arumage says:
05:13 AM, 09/ 3/08
Turbocharged cars create their own atmosphere so they're not affected by altitude in quite the same way as a normally aspirated engine.
dougtheeng says:
08:24 AM, 09/ 3/08
My family owns 2 x 2004 VW Golf TDIs and I you should definitely be warned that the fuel needle is very misleading. I can go for 1/4 of the tank before it even begins to move down. The second half of the tank goes much, much faster then the first. I would advise using the fuel gauge in addition to the trip odometer reading.
joefrompa says:
08:43 AM, 09/ 3/08
2nd what arumage said, except I believe they dump more fuel while maintaining their own atmosphere by increasing overall boost.
Great post - Shame you describe the experience as boring. I'm waiting for a non-boring diesel that gets 35+mpg while climbing 5000 feet...
Joe
matt_a says:
12:54 PM, 09/ 3/08
It's interesting that this TDI doesn't seem to have that high of a range. My 2001 Golf TDI can usually hit between 650-700 miles before needing a fill up. If I drive it like a stole it, I'm at half a tank at 350 miles. Last tank, I got 44mpg.
One thing I always do is vent the tank when I fill it up. If you look on tdiclub.com, you'll find many mentions of the 'ventectomy'. You can squeeze in an additional 2 gallons this way.
firstwagon says:
07:36 PM, 09/ 3/08
I asked a co-worker today how far his Jetta wagon goes on a tank and he replied 1000km give or take.
That's about 620 miles.
Almost twice what my Legacy wagon does on the same size tank.
I can't wait for the new Subaru diesel.
karjunkie says:
09:03 AM, 09/ 4/08
firstwagon: why wait? buy the new jetta sporswagen tdi instead. Speaking of which, when are you guys at insideline going to add the new sportwagen to the long-term fleet?