Source
r/tdi•
MTBSPEC

Help with diesel algae

I have a 2010 VW Jetta tdi. I have been told by vw that I have such a bad diesel algae problem they quoted me $6,500 to replace the entire fuel system. Obviously I didn’t buy this. A couple of months ago I did pay to have the tank drained and cleaned after they discovered it. Since then I have been having some trouble starting. Mostly slow or sluggish starts that are exacerbated by the cold. It runs fine although I think I’m getting poor mpg. I finally pushed vw to get me a resolution to the start problem and they said the algae growth has come back and I probably need to replace the whole system. Since it still runs decent, is there anything I else I can do to help get some more life out of this? I only have 145,000 miles on it. Thanks

Posted Mar 31, 2022, 2:07 AM UTC

218
Ohhbee1•

Try changing fuel filter if you haven't already and get a bottle of bio kleen.

3
MTBSPECOP•

The fuel filter was changed when they cleaned the tank.

2
Ohhbee1•

Bio kleen for sure. Don't be afraid of the tried and tested additives. It'd be hard for you to find someone on here that doesn't use some form of additive with every fill up.

3
FunclePinky•

This is what happens when you drive around with an empty tank most of the time. Keep the fuel tank as close to full as possible and you won't have that problem.

2
MTBSPECOP•

I think it could be from not driving it enough. I drive about 10k in a year but that is heavily skewed towards trips. It typically sits for 3-4 days at a time, but usually not more than a week.

1
BjDrizzle69•

Fuel age and treatment. Once you get it, it’s kinda difficult to completely get rid of it without replacing everything fuel touches. Use treatments change your filter afterwards. If you’re out of warranty get a nictane filter.

1
Oilers02•

Ats fuel cleaner

1
MTBSPECOP•

I will check that out. I get nervous about additives since tdis seem so touchy.

1
jamesrainsgames•

You do realize that algae is worse for your engine than any additive? Sorry I just think it's funny that you have algae growing in your tank and you're worried about an additive ruining your engine instead of the carbon the algae is going to leave in your cylinders

0
MTBSPECOP•

I’m just trying to get things right. I’m not avoiding additives.

1
demonic3•

If you have deleted the dpf. I would suggest running transmission fluid at high concentration. If you still have the filter. Run amsoil injector cleaner.

1
Ohhbee1•

Did the vehicle sit for a long time without being driven at some point. Until yesterday I never knew "algae" was a thing. Seems like it'd have to take a while before that became a problem.

1
MTBSPECOP•

Not really. Just infrequent driving but I do not know of anytime it sat for extended time. I have not owned it since the beginning but I bought it from the original owner, who I also know. So I am fairly confident about that.

VW made it sound like it came from a bad batch of diesel originally but now they are making it out to be more of a chronic problem.

1
Ohhbee1•

These cars like long commutes. It's possible he or she didn't have that or it sat while under their ownership. Or, it's entirely possible they filled up at the same fuel station and that fuel station had an algae problem in their fuel tanks.

Heavy dose a treatment specifically for the algae issue for a few tanks from a station that has high use and not some mom and pop gas station in the middle of nowhere. I'm always worried about stopping at a station that doesn't see a lot of traffic, I've gotten too many bad tanks of fuel (gas and diesel).

1
Noxidnai•

This is interesting. It seems like the algae would need moisture to grow. Moisture in diesel is certainly a real thing. What climate do you live in? Somewhere hot and humid?

I don't think the VW filter does a good job of separating water. I've never got water out of my fuel filter housing.

1
MTBSPECOP•

I live in Indiana. So kind of? But not exactly famously humid.

I think VW punted a little bit on trying to figure it out and just threw the kitchen sink at it knowing I would say no. They had previously replaced my engine speed sensor, claiming that was going to solve the problem and it didn’t.

1
Noxidnai•

I'm in TN, which is probably more humid. Never seen water.

I don't think the dealer is wrong to say you need to replace everything and since everything is a lot of stuff it is expensive. From their perspective they can't half arse it.

I would do what others suggest and keep the tank full, use some additive and drive it frequently.

1
smithmsdjsx•

Maybe get a can of Diesel purge? Not sure tho...

0