Filled up with petrol instead of diesel?

At a glance: Even small amounts of petrol damage modern diesel engines (common rail and unit injector from 1999 onwards). Do not start the engine; if it is already running, stop at once and switch it off. The high-pressure pump, injectors and seals are particularly at risk, because petrol washes away the lubricating film and metal shavings can form. We pump out the tank on site and, if necessary, flush up to the high-pressure pump – around the clock: 0177 3555403.

Petrol in a diesel tank: One moment of inattention is all it takes to fill up with the wrong fuel—in this case, petrol in a diesel tank. Even a small amount of the wrong fuel can damage your engine. If you have filled up with petrol instead of diesel, do not start the engine. If you have already started it, stop as soon as possible and switch off the engine.
If you have an older diesel vehicle (not a direct-injection engine), your engine may tolerate a small amount of petrol. However, petrol is very harmful to common-rail and unit-injector diesel engines manufactured from 1999 onwards.

Mobile Fuel Draining Service - Immediate On-Site Assistance - 24 Hours

0177 3555403

Filled up with petrol instead of diesel? What are the symptoms?

Depending on the engine and the amount of wrong fuel, the following symptoms are typical: Diesel engines that have accidentally been filled with petrol will usually make a loud knocking noise. 

Symptoms in detail

  1. Rough idle (engine not running properly on all cylinders)
  2. Engine sputtering
  3. Engine knocking
  4. Check engine light comes on or flashes
  5. Engine won’t respond to the accelerator
  6. Engine won’t start, depending on how many liters of the wrong fuel entered the tank 
  7. Loss of engine power 
  8. Unusual exhaust smoke
  9. Engine sputters after starting.
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Affected components

  • High-pressure fuel pump: Diesel high-pressure pumps are lubricated by the diesel fuel flowing through them; petrol does not provide this lubrication. The high-pressure pump may seize or become stuck.
  • Fuel injectors: Diesel injectors are not designed for petrol. Metal shavings produced by the high-pressure pump can damage the injectors. 
  • Timing belt/chain: If the high-pressure pump seizes, it can affect the engine timing belt or chain, or even cause it to break, resulting in major engine damage.
  • Fuel lines and seals: Diesel fuel lines and seals are not designed for petrol. Petrol is corrosive and can damage fuel hoses and seals.
  • Engine control unit (ECU): The engine control unit precisely manages all functions required for engine operation. The electronics control fuel injection. The wrong fuel can cause sensors and components to log faults or put the engine into limp mode.

Mobile Fuel Draining Service - Immediate On-Site Assistance - 24 Hours

0177 3555403

Petrol in a diesel tank: regular or premium petrol

Do not start the engine under any circumstances. Have a professional drain the fuel mixture. Never try to empty the tank yourself (risk of explosion from highly flammable fuel mixtures and electrostatic discharge). If the engine has not been started with the wrong fuel, draining the contaminated fuel from the tank is sufficient.

If you continue driving with the wrong fuel, repairs can cost several thousand euros. The entire fuel injection system may need to be replaced, along with the high-pressure pump, injectors, fuel lines and tank. Diesel high-pressure pumps are lubricated by the diesel fuel flowing through them; petrol does not provide this lubrication. The high-pressure pump may seize or become stuck.

As a result, a seized pump can affect the engine timing belt or chain, or even cause it to break, resulting in major engine damage. If your vehicle is equipped with a particulate filter (FAP), the much higher combustion temperatures of petrol can also destroy it. 

Further information:

Mobile Fuel Draining Service - Immediate On-Site Assistance - 24 Hours

Fueled up with the wrong fuel in your area? We pump out your tank on-site in Düsseldorf & surrounding areas, the Bergisches Land, Köln, Krefeld & Aachen, the Ruhrgebiet and Niederrhein. All locations and service areas: Locations & Service Area.

Frequently asked questions

Can I keep driving with a little petrol in my diesel?

No. In common-rail and unit-injector diesels built from 1999 onwards, even small amounts of petrol cause damage. Only older diesels without direct injection tolerate a little petrol. Do not start the engine; if it is already running, pull over and switch it off immediately.

How do I notice petrol in a diesel?

Typical signs are heavy knocking, rough running, jerking, loss of power, unusual exhaust smoke and the engine warning light. Depending on the amount, the engine may not start at all.

Which parts are at risk?

Above all the high-pressure pump and injectors: petrol does not lubricate, so the pump can seize and shed metal particles. Fuel lines and seals suffer too. In the worst case the timing belt or chain breaks.

What does pumping out cost?

On-site pump-out costs from €95 incl. VAT, usually around €300 including call-out and disposal, never more than €600. We give you the fixed price by phone in advance: +49 177 3555403.

How quickly can you be there?

Around the clock: in Düsseldorf usually within 15 to 35 minutes, elsewhere in NRW generally within 30 to 45 minutes. Pinar Abpumpservice has been operating since 2015; owner Mustafa Karapinar has worked in the motor trade since 1986.

Free consultation