Fuel additive LIQUI MOLY 21317
- EAN: 4100420213175
- Volume [Liters]: 1
- Container type: Box
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- Product line: P004770
- Brand: Liqui Moly
- Model: 21317
Purpose and Specifications
LIQUI MOLY 21317 Anti-Bacterial Diesel Additive is a powerful 1-liter tin container solution designed to kill bacteria, yeasts, and molds in your diesel fuel system. It prevents diesel pest - that jelly-like gunk from biofuel that clogs tanks in rarely used vehicles like RVs, trucks, or construction equipment. Add it to protect injectors, reduce emissions, boost lubrication, and keep your engine running smooth without costly breakdowns.
- Works in all diesel engines, including those with particulate filters
- 1 liter treats up to 300 liters of fuel
- Effect lasts up to 2,000 km
- Safe for long-term storage, even in cold down to -20°C
- Shelf life: 4 years unopened
When to Use / Replace?
Use preventively every 3-6 months or 10,000 km if your vehicle sits idle often, like seasonal RVs or work trucks. Pour in one full bottle when refueling to stop bacterial growth before it starts. Replace at next service if contamination is suspected - it decontaminates infested tanks fast. Ideal before winter storage to avoid fuel system corrosion from moisture.
Frequently Asked Questions
Is it safe for my DPF-equipped diesel? Yes, fully tested and compatible - cleans without harming filters.
How much do I add per tank? One 1L bottle for 300L fuel; effects protect for 2,000 km driving.
Can I use it year-round? Best for infrequent use or storage, but safe anytime to maintain clean fuel.
Shipping & delivery
We deliver across the European Union. Orders confirmed on business days are prepared and handed to the carrier the same or the next business day.
Delivery methods
Courier delivery to your door, or pickup at parcel lockers and points across our carrier networks.






Delivery time
Usually 1–5 business days, depending on destination and carrier.
Shipping cost
Calculated automatically at checkout by weight and destination. Free shipping may apply above a store-specific order value.
Packaging — built to arrive intact
Oil and lubricants are liquids, so we pack every order to reach you perfectly. This is the care that goes into each parcel:
The result: a clean, sealed, undamaged parcel — because getting the oil to you intact is the whole point.
Returns
14-day right of withdrawal under EU consumer law. Items must be unused and in original, unopened packaging.
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