Purpose and Specifications

LIQUI MOLY 5139 Common Rail Additive is a premium diesel fuel treatment designed for modern diesel engines with Common Rail and pump-injection systems. This 250 ml can treats up to 75 liters of low-sulfur diesel fuel at a simple 1:300 ratio, delivering protection that lasts up to 2,000 km.

It boosts fuel lubricity to cut wear on high-pressure injectors, cleans deposits from the entire fuel system including injectors and combustion chambers, and improves cold starts by enhancing ignition. Expect smoother engine running, lower soot emissions, better fuel economy, and longer life for your diesel particulate filter (DPF). Safe for turbochargers, catalytic converters, and DPF systems, it's perfect for city driving and short trips where engines don't fully warm up.

• Increases cetane for reliable cold-weather starts down to -10°C and better combustion
• Provides strong corrosion protection during storage or extreme conditions
• Reduces fuel use and exhaust odors for cleaner, quieter performance
• Shelf life: 4 years unopened in cool, dry storage

When to Use / Replace?

Add every 2,000 km or with each tank for preventative care, especially with low-sulfur fuels that lack natural lubrication. Ideal for daily drivers, fleet vehicles, or stored engines. Pour directly into the fuel tank before filling up – it mixes automatically. Replace treatment interval aligns with mileage; one can per 75 liters keeps your system protected without overlap.

FAQ:

Is LIQUI MOLY 5139 safe for all diesel engines?
Yes, it's formulated for all diesel engines with Common Rail or pump-injection, including those with DPF and turbochargers. Tested safe for emissions systems.

How much fuel does one 250 ml bottle treat?
One bottle handles up to 75 liters of diesel, with effects lasting 2,000 km or until your next fill-up and add.

Can it help with poor cold starts or smoky exhaust?
Absolutely – it boosts cetane for easier cold starts and cuts soot by cleaning injectors and optimizing combustion.