It doesn't usually happen this way.
I was about a mile from my house yesterday when the 2005 Volkswagen Jetta TDI began to sputter. It wasn't horrible, more like a ragged feel as I accelerated into the higher RPMs.
We've been running the V-Dub on B99 biodiesel (99 percent biodiesel and one percent petrodiesel) and were warned that the fuel filter might get clogged. Biodiesel dissolves deposits in the fuel system that flow into the filter and gum it up. This is exactly what it felt like when I tried to accelerate.
Luckily, I had already purchased two fuel filters so I was ready for this moment. I got my tools and the new filter and made the switch. It only required a screw driver (to loosen the filter bracket) and pliers to pinch the hose clamps. The filter must have been on there a long time because the hoses were sealed tight to the fittings and were hard to break loose. But it only took 10 minutes and I was back in the car, ready to fire it up.
Philip Reed, Edmunds.com Senior Consumer Advice Editor @ 59,735 miles
The Jetta started up again, no problem, and I kept the revs high to try to fill up the new filter. Then, it suddenly cut out and wouldn't restart. I drained some of the clean diesel from the old filter and topped up the new filter. It restarted and ran smoothly.
I then completely drained the boidiesel from the old filter into a glass and poured it through a coffee filter I put in an old transmission funnel. It smells completely different than petrodiesel, more like paint thinner. There were very small flecs of black left on the filter which were smaller than grains of sand. I wondered if this was the dissolved solids from the fuel system. I wanted to cut open the old filter but its was like a bank vault. That's German engineering for you.
So, the TDI is back on the road again and it ran smoothly on my 31-mile commute to the office this morning. I still have one clean filter in case if fouls again.
karjunkie says:
08:43 AM, 08/ 1/08
I suspect the old filter was already pretty gunked up. Maybe a repair shop can cut it open for you. I am willing to bet you don't need to use that second filter until many more miles. Have you noticed any improvement in performance or MPGs?
texases says:
10:17 AM, 08/ 1/08
I'd be really curious what those 'little black flecs' are - anybody there got a hacksaw?
skierx420 says:
10:31 AM, 08/ 1/08
I'll bet the fuel filter failure was probably going to happen anyway. I'd be willing to bet that it is the original. I hope that the B99 is going to really pick up some mileage (.5 mpg) now with a clean and easy way through the filter.
stingray454 says:
11:08 AM, 08/ 1/08
Yeah, that old filter was overdue for a change anyway if it was original. Fuel filters should be changed every 30k miles. Most owner's manuals leave out the fuel filter as a maintenance item.
You gotta love easy fixed like this though. It was smart of you to keep an extra fuel filter on board, and some tools to change it. Always good to have a contingency plan.
joefrompa says:
07:14 AM, 08/ 4/08
Stingray - Are you referring to diesel engines specifically?
I know plenty of cars nowadays have an in-tank fuel filter that is supposed to be "life-time".
Joe
volkstrooper says:
11:57 AM, 08/ 5/08
Hey there, I'm a bit confused as to how you drained your old filter. Did you unscrew the bottom of the filter and then use that to fill your new filter? Because if you did you just filled up your new filter with water. The Fuel filter separates water from the fuel, in addition to catching the dirt particles that may be present in the fuel, and the drainage at the bottom releases that water.
bionick says:
02:32 AM, 08/ 7/08
Just starting with B100 on my polo TDi. How many KMs or tanks before I should change the fuel filter. Will once be enough?
banhugh says:
02:50 PM, 09/29/08
Was it french fries that had clogged the filter or onion rings?