What % of Biodiesel in an 02 Jetta TDI

Varmit_Express · May 23rd, 2006, 07:38

Hello,

I'm new to the Volkswagen TDI, I just purchased a 2002 Jetta and was wondering what % of biodiesel I can run though it without any problems. I'm not worried about the warranty issue just mechanically. I have access to B99 here locally so any % should be easy to mix up. I dont want to start any biodiesel good/bad posts. I'm going to run it so I just want a %. Thank You.

Varmit_Express

ScorpionBoy · May 23rd, 2006, 07:53

run b5, that is what VoA recommends.

MrErlo · May 23rd, 2006, 08:02

i am on tank 2 of B20 right now. it seems to be doing very well. i plan on stepping up to B50 for my next tank, and then B75, B99. i've been told to take steps to avoid the fuel filter becoming clogged all at once.

you should update your personal information to include your location, that way gurus in your area can help you with small maintenance and mods.

riofrio · May 23rd, 2006, 10:08

Quote:

Originally Posted by MrErlo

i've been told to take steps to avoid the fuel filter becoming clogged all at once.

Yeah, but arguably the converse might be more convenient. If you jump right into B99, you'll clean all the gunk out faster and you'll only have to change your filter once or twice. I'm having the same dilemma myself, as I am about to get my first batch of bio this weekend.

Hobhancock · May 23rd, 2006, 10:42

I am on my third tank of B100 homebrew. No performance issues at all. MPG's are the same as Dino. Ready to change the filter now. Just reading another thread on the cost of Bio around the country, we produce it for ourselves for .60 a gallon. Its awesome. No warranty issues to deal with since I have no warranty from VW. We have been brewing since October 2005. I run it also in my Ford Excursion. Bought the Jetta since I commute farther now. My wife loves it so much I dont drive she does. It has been better for her not having to drive around the behemouth Excursion for errands. The Jetta fits her better anyway. The days I dont stop to pick up oil I drive the Excursion. Sure wish I could afford another TDI. I would go for the 5 speed Golf 4 door if I could.

B100 · May 23rd, 2006, 10:49

How many miles previously on the car? Was it always run on petroleum diesel? In any case, plan to change fuel filters a couple times as old deposits are cleaned out of the tank. You should have no problem running on B100 right away, just watch seals and hoses. take off the engine cover, and make sure the injection pump is dry now, and stays dry over time. Watch out for any bubbles in your clear fuel line while idling (a small bubble before you start is okay).

Gothmolly · May 23rd, 2006, 13:30

I switched to B20 at 57k when I bought the car, no fuel filter clogs, no performance issues, no leaks, nothing but some cold-start problems when I forgot the proper additive.

MrErlo · May 23rd, 2006, 14:27

what addatives do you all use to avoid cold start problems? i know it's summer now, but i want to make sure i'm ready come fall/winter.

i'm currently putting Stanadyne Performance Formula into every tank.

Audi5000TDI · May 23rd, 2006, 18:24

http://pics.tdiclub.com/data/3005/3093BD_TSB.pdf

It's all in there, everything you need to know.

P-car · May 23rd, 2006, 19:05

I run B100 whenever the weather allows and I have it. I run less in cool weather and B0 in winter. If something breaks on my cars (and because they are VW's something will) I fix them. I am an adult and take full responsibility for my actions.

Congrats on your purchase and enjoy you car.

k1rod · May 23rd, 2006, 20:51

Quote:

Originally Posted by Audi5000TDI

http://pics.tdiclub.com/data/3005/3093BD_TSB.pdf

It's all in there, everything you need to know.

I don't even know anyplace that sells B5 and it certainly wouldn't be worthwhile driving 40 miles roundtrip to buy 1 gallon of B100 to mix with my 14 gallons of D2. I also understand that Biodiesel doesn't store that well so filling a tote that I draw 1 gallon per tankful probably wouldn't be a good thing.

So, I split it half and half (B50). I'll do the experiment. If my injector pump or injectors crap out, I'll replace them. I'll also have a valuable data point (either way) to contribute to the knowledge database here.

I do hear lots of theoretical warnings (ie your IP will leak/fail, your injectors will clog, you'll get lot's of CEL's, your whole damn car is going up in a raging purple ball of fire) but I see very few posts from people saying that these things have actually happened to them. At least not at a rate appreciably different than the D2 "control group" Yes I understand there are far fewer people using bio and my observations are normalized to that fact.

I also see no rigorous theoretical explanations for the dire warnings. My IP will die? Why exactly? I understand that the lubricity of bio ie even better than D2. Somebody please tell me the failure mode of an IP using say, B50. Somebody explain why my injectors are going to clog using commercial, high quality B50 (somebody did warn me that might be an oxymoron but I'm still not sure why?)

If the folks that keep slamming bio would throw out some hard data instead of speculation, conjecture, and VW's rules (for which we have no insight into what their reasoning was when they made them) we would all be in a much better position to weigh the risks.

The Audi5000TDI guy keeps telling us about VW's position on this issue, but we already know VW's position. Some of us speculate that VW doesn't know the answers for sure and just hasn't come to the place where they are willing to risk late term warranty repairs it if it turns out that B100 causes a 0.9% greater in-warranty IP failure rate. We on the other hand may be willing to risk it. Robert51?? works on lots of TDI's and apparently sees lot's of CEL's. But CEL's for what? Are these easily repairable problems? Are they more prevalent with people Using B100 than people using B20? Do they infact turn out to be fuel system related. Do they go away when switching back to D2? I sure would appreciate knowing.

The problem, and the reason there is so much contradicting information, is that we for the most part all we are getting is speculation and opinions and very little data.

B100 · May 23rd, 2006, 21:20

Quote:

Originally Posted by k1rod

I also see no rigorous theoretical explanations for the dire warnings. My IP will die? Why exactly? I understand that the lubricity of bio ie even better than D2. Somebody please tell me the failure mode of an IP using say, B50. Somebody explain why my injectors are going to clog using commercial, high quality B50 (somebody did warn me that might be an oxymoron but I'm still not sure why?)

If the folks that keep slamming bio would throw out some hard data instead of speculation, conjecture, and VW's rules (for which we have no insight into what their reasoning was when they made them) we would all be in a much better position to weigh the risks.

The problem, and the reason there is so much contradicting information, is that we for the most part all we are getting is speculation and opinions and very little data.

I know what you mean. I was talking with a mechanic over Mother's day picnic. He's been at it for thirty years, works on a wide variety of cars in San Francisco at an independent garage. He loves TDIs... but when I told him I ran biodiesel in the car, his face simply sank, and the tale of woe began. ...He's seen too many cars come in with fouled fuel systems... blown injector pumps... etc., etc., sounding just like AudiTroll. The best he could come to a factual assertion was that injection pumps have sensitive internal sensors that are tuned for the viscoscity of D2, and would fail, definitely, absolutely, on biodiesel.

He had no hard evidence, just strong feelings. He couldn't tell me whether the TDIs he had seen were running B5 or B100, whether super-clean homebrew, or crappy batches full of glycerin, OR whether they had seen bad batches of D2.

He did, however, have some advice (apart from urging me to stop using any biodiesel if I cared at all for the longevity of my engine). He suggested I add a quart of Marvel Mystery Oil to every tank of fuel, would reduce clatter and help clean injectors. I kid you not... he was glad to trash biodiesel, but perfectly happy to suggest I throw in snake oil.

RC · May 24th, 2006, 02:53

Quote:

Originally Posted by B100

... In any case, plan to change fuel filters a couple times as old deposits are cleaned out of the tank.

With all due respect... This fuel filter clogging thing is the so overblown it isn`t funny. Yes, some may need a filter change out, perhaps they were due anyway but it is nowhere near prevelent as some would suggest. And it certainly doesn`t need to be changed out repeatedly... as long as you are using good quality fuel.

Put B99 in the tank and go.

B100 · May 24th, 2006, 07:37

Quote:

Originally Posted by RC

With all due respect... This fuel filter clogging thing is the so overblown it isn`t funny. Yes, some may need a filter change out, perhaps they were due anyway but it is nowhere near prevelent as some would suggest. And it certainly doesn`t need to be changed out repeatedly... as long as you are using good quality fuel.

Put B99 in the tank and go.

You're right, it's not as though every driver switching to B100/99/whatever will see clogged filters. I should have said "be prepared to change the filter" if the car exhibits hard starting or driving problems. I have seen a filter soiled by a single tank of bad petro diesel, inbetween otherwise high percentages of biodiesel in my Golf.

compu_85 · May 24th, 2006, 07:49

More important then the % of bio you want to run is the quality. Bad fuel, be it petro or bio, will screw up your fuel injection system.

I get my biodiesel from a high quality source and regularly run up to b99, and have had zero problems since I switched at 140,000 miles.