Diesel fuelTreatment

I am a a relatively new diesel owner. Last year I had trouble with algae in the tank. Would up an expensive fix.
Now I do not go below 1/2 tank of fuel.
I am in Fl so no really cold weather.
Now I am beginning to experience some of the same early signs of trouble. Running rough around 1250 rpm.
2003 ford f-350.
I know I need to put a treatment in the fuel tank but there are so many to choose from!

Any diesel cleaner with an algicide should work. Fuel storage tanks at stations are notorious for bacteria microbiomes which is a leading cause of fuel leaks in oil refineries and gas stations. My concern here is that the station where you fuel up is not maintaining their tanks.

Are you sure there is bacteria in your fuel? There are plenty of other issues that can clog filters and fuel lines.

Is this a 7.3 or 6.0 PS? I have an 02 7.3 and the first thing I would do is check the fuel tank strainers as well as the fuel filter/bowel.

First thing I would do is test for water in your tank. Even without the fill station not maintaining their stuff, you can have water in there from condensation or otherwise.

Thanks all. Like I said, I had a similar issue last year and it was diagnosed as algae, which clog two fuel injectors. Tank was treated then. I have a water gauge on my dashboard, which shows if I have too much water in my tank. It is a 6.0, but all the necessary fixes has been done. pardon the grammatical errors, as I am speaking to text as I drive to the store. Also, I buy fuel at a variety of stations. This is a very rural area around Ocalla with lots of diesel trucks and lots of easels station.

Did the water gauge give you a heads up the first time?

I don’t trust dash gauges - they’re called dummy gauges for a reason. :slight_smile:

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Technically, they can only diagnose algae if they culture. I don’t think many mechanics are capable or have a microbiology capability. It isn’t technically “algae.” It is a mix of sulfur and metal reducing bacteria and fungi that create a “film” that clogs filters.

You can get test strips that will tell you in 3-4 days or you can run pH on the fuel to see if it is acidic. Fuel tends to be neutral.

I would be more inclined to look at stiction and injector contribution. Or even a fuel lifter pump that is going.

If you have too much water in the fuel your fuel separator bowl may have issues or something as simple as a bad filler cap (allows humidity to accumulate in the tank each night).

But diselkleen has an algaecide additive you can try.


A friend keeps a jar in her truck to check the diesel for water before filling up (something about the color). She just posted about getting a bad batch of diesel with water in it in Ocala. Don’t know where.

ETA: it was the Love’s north of the WEC exit on I-75

It may be something as simple as too much water in the diesel fuel being sold. You are running diluted diesel.


wow good to know! Fortunately the other side of town from me…

I would pH test the fuel.

Next, I would add an auxiliary fuel filter and fuel water separator - the stock one is garbage. I have these on my truck, with a gauge between the filters and the HP pump (CP3) so I know when they’re fouling. These should give you some leeway before you end up with messed up injectors again.

Can you bleed off some fuel from your filter? Catch it in a jar, see if there’s water.

Also, pull your filter canister to take a look? Assuming it’s stock, if you have biologics, the filter will be black instead of bright yellow/greenish.

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Inquiring minds would like to know what she does with the jarred diesel… maybe she has a funnel for her tank? :joy:

Yes, if it’s good, she puts it in the tank. The bad diesel, she showed to the people at the station, and they kept it, so I guess she got a new jar.

She started doing this after major engine repair work was needed after getting bad fuel.


Well thanks y’all but I do not have the skills to do any of this except add the treatment to the tank.
I plan to do that this weekend and let it idle for a whale and see what happens.
Thanks again.

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