Petrol in a Diesel Car What to Do
Putting petrol in a diesel car is one of the most common and serious misfuelling mistakes.
What you do next can be the difference between a quick fix and major engine damage.
This guide explains exactly what to do if you’ve put petrol in a diesel car, what damage can occur, and when to call for professional help.
First things first – Do NOT start the car
What to do immediately if you put petrol in a diesel car
If you realise you’ve put petrol in a diesel vehicle:
Do NOT start the engine
Do NOT turn the ignition on
Do NOT attempt to drive
Call a professional wrong fuel recovery service immediately
If the engine has not been started, serious damage can often be avoided.
Why petrol in a diesel car causes damage
Diesel fuel provides lubrication for critical engine components.
Petrol does not.
When petrol enters a diesel fuel system it can:
Strip lubrication from fuel pumps
Damage high-pressure injectors
Cause metal-to-metal contact
Lead to catastrophic fuel system failure
Modern diesel engines are especially sensitive due to high-pressure systems.
What happens if you drive a diesel car with petrol in it?
Starting the engine allows petrol to circulate through the system.
This can result in:
Injector failure
Fuel pump damage
Engine stalling
Contaminated fuel lines
Very expensive repair bills
In some cases, continued driving can require full fuel system replacement.
Is a small amount of petrol in a diesel car dangerous?
Even a small amount of petrol can cause issues if the engine is started.
Risk depends on:
How much petrol was added
Whether the engine was started
How long the vehicle ran
Because the risk is unpredictable, professional assessment is always recommended.
Can the car be repaired?
Yes — in many cases.
If dealt with early:
The fuel tank can be drained
The system flushed
The correct diesel fuel added
The vehicle returned to normal operation
The earlier the response, the better the outcome and the lower the cost.
Common mistakes to avoid
Do NOT:
Try to “dilute” the petrol with diesel
Drive the car to “burn it off”
Start the engine “just to check”
Attempt DIY draining
These actions often turn a simple fix into a major repair.
When to call a wrong fuel specialist?
You should seek professional help if:
Petrol has been added to a diesel car
You’re unsure if the engine was started
The vehicle won’t start
Warning lights appear
A specialist can advise you immediately and attend your location if required.
Put the wrong fuel in your car? Don’t start it.
24/7 Emergency Wrong Fuel Recovery
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