Accidentally putting diesel in a petrol car can be a frightening experience. This comprehensive guide explains exactly what happens and the steps you need to take to protect your vehicle from serious damage.
Quick Answer:
If you’ve put diesel in a petrol car, DON’T START THE ENGINE. Even a small amount of diesel can damage your petrol engine.Contact a professional fuel drain service immediately. If you haven’t started the engine, the fix is usually straightforward and causes no lasting damage.
Contents
Immediate Effects of Diesel in a Petrol Engine
When diesel enters a petrol engine system, several problems can occur:
- Diesel fuel is thicker and oilier than petrol
- Petrol engines cannot properly atomize diesel fuel
- The fuel injection system may become clogged
- Spark plugs can become fouled and fail to ignite
Severity Based on Amount Mixed
| Misfueling Scenario | Potential Consequences | Recommended Actions |
|---|---|---|
| Diesel in a Petrol Engine | Damage to fuel pump, filter, and injectors | Turn off engine, drain tank, and seek professional help |
| Petrol in a Diesel Engine | Wear on fuel pump, filter, and injectors | Turn off engine, drain tank, and seek professional help |
| Regular Fuel in a Premium Fuel Vehicle | Reduced performance and fuel economy | Add premium fuel to dilute the regular fuel |
By taking these steps, you can avoid misfueling and save your car from expensive repairs.
Warning Signs of Diesel in Petrol Engine
If you’ve accidentally started the engine, watch for these symptoms:
- Excessive smoke from the exhaust
- Engine misfiring or stuttering
- Significant loss of power
- Strong diesel smell
- Engine warning light activation
Immediate Steps to Take
- Don’t Start the Engine
- If you realize before starting, leave the key out
- If running, stop immediately in a safe location
- Document Everything
- Note how much diesel was added
- Record time and location
- Take photos for insurance
- Contact Professional Help
- Call a specialized fuel drain service
- Contact your insurance provider
- Arrange for vehicle recovery if needed
Prevention Tips
Avoid this costly mistake by:
- Double-checking the fuel nozzle color (black for diesel, green for petrol)
- Reading pump labels carefully
- Installing a misfueling prevention device
- Using fuel cards specific to your vehicle type
Cost Implications
The financial impact varies depending on quick action:
- Fuel drain service: $150-300
- Full system flush: $500-1000
- Engine repair (if started): $2000-4000+
- Complete engine replacement: $4000-10000+
Frequently Asked Questions
Can I just add petrol to dilute the diesel?
No, adding petrol won’t solve the problem and could cause additional damage. The entire system needs proper draining.
How long does a fuel drain take?
A professional fuel drain typically takes 30-60 minutes when performed by qualified technicians.
Will my insurance cover misfueling?
Some comprehensive policies cover misfueling, but many don’t. Check your policy details or contact your provider.
Can I drain the fuel myself?
DIY fuel draining is not recommended as it requires specialized equipment and proper disposal methods.
Conclusion
While putting diesel in a petrol car is a serious mistake, quick action can prevent lasting damage. Remember: don’t start the engine, call professionals immediately, and consider installing preventive measures for the future.