If you think you put the wrong fuel in a rental car, stop refuelling and do not turn on the ignition or start the engine. If you are already driving, stop somewhere safe, switch off and do not restart. AA and RAC guidance agrees on this immediate priority. [8] [6]
This guide covers petrol in a diesel vehicle or diesel in a petrol vehicle. It is not a guide to changing octane grades, LPG systems or EV charging. For a rental, there are two separate jobs: prevent further circulation of the wrong fuel, then get the vehicle supplier's instructions for recovery. A return deadline does not make the car safe to drive.
1. At the pump: leave the ignition off
Tell the station attendant what happened. Do not start the car just to free the pump, test whether it runs, or move it a few metres. RAC specifically advises keeping the ignition off. Ask station staff and the authorized recovery service to arrange safe movement; do not experiment with a rental car's gear-release controls or push it into traffic. [6]
If there is spilled fuel, fire or another immediate danger, move away and follow station staff and local emergency-service instructions. Document the incident only when safe. Do not siphon or drain fuel yourself.
2. Tell the supplier which state the car is in
| What happened | Next action | What to report |
|---|---|---|
| Fuel added, ignition never switched on | Keep it off and ask for authorized recovery. | Fuel type, approximate amount, location. |
| Ignition switched on, engine not started | Switch it off; do not test-start. | Say the ignition was on, not just that you did not drive. |
| Engine started or car driven | Stop safely, switch off and do not restart. | Approximate distance, symptoms and current location. |
| Not sure which fuel was added | Keep the car off while the receipt and pump label are checked. | State the uncertainty rather than guessing. |
Petrol can reduce the lubrication diesel fuel provides to the fuel system. Diesel in a petrol vehicle can also cause problems; it is not permission to drive. Neither the absence of a warning light nor a small quantity proves that your particular vehicle is safe. [8]
3. Send one useful recovery request
Use the supplier contact in your rental agreement or booking confirmation. For an Orcar booking, check those booking details rather than an unverified number in a search advertisement. Prepare:
- Booking reference and vehicle registration, shared privately with the verified supplier.
- Station name, exact location and a safe callback number.
- Required fuel shown on the vehicle label, fuel actually selected, litres and time from the receipt.
- Whether the ignition was on, the engine ran or the car moved.
- Your return or flight deadline, to plan alternatives without promising a repair time.
When safe and permitted at the station, retain the receipt and photograph the relevant labels. Keep payment-card details and unrelated people out of shared images. A short message can be:
I may have put the wrong fuel in this rental car. Please confirm the authorized recovery provider, where the vehicle should go and whether I must approve any charges before work begins. I will send the location, receipt and ignition or driving history privately.
4. Separate recovery permission from cost coverage
Ask the supplier to confirm who may tow or drain the vehicle, the approved destination, whether inspection is required before driving again, and how to handle the rental's return. If a third party offers help, verify authorization before agreeing to non-emergency work.
Do not assume collision damage protection, roadside assistance, a card benefit or travel insurance covers misfuelling. Ask the relevant provider which terms apply to this incident, whether prior approval is required, and which evidence to retain. Request an itemized estimate and written instructions. This article does not establish an Orcar coverage rule, repair price, replacement-car entitlement or completion time.
Keep the original receipt, incident reference, recovery destination, approvals and final invoice together. The record should distinguish the fuel purchase, recovery and any repair, not reduce them to one unexplained charge.
5. Prevent a repeat at the next fill-up
Read the vehicle's fuel label and the pump's written fuel name, not just the nozzle colour. AA explicitly warns against relying on hose or nozzle colour. In Korea, 휘발유 means petrol/gasoline and 경유 means diesel. If the vehicle label, contract or pump leaves you uncertain, ask before filling. [8]
For normal refuelling, use our Korea gas-station guide. The fuel-policy guide covers return fuel levels, a separate question from contamination. If recovery changes your return plan, revisit the rental-return checklist with the supplier's instructions.
Frequently asked questions
Can I dilute the wrong fuel with the correct fuel?
Do not treat topping up as a repair. Leave the car off and have the authorized professional assess it. This guide deliberately gives no universally safe quantity or mixture ratio.
Can I drive back if the rental office is nearby?
No distance is a reason to test the car. Keep it off, or stop safely if already driving, and arrange recovery with the supplier. [6]
Do the AA and RAC telephone numbers work for recovery in Korea?
The linked pages describe UK services. We cite their mechanical safety guidance, not a Korean dispatch service. Use the contact designated in your rental documents for the country where you are driving.
Sources checked 21 September 2026: AA wrong-fuel advice [8] and RAC wrong-fuel recovery guidance [6]. Supplier-contact and evidence checklists are Orcar editorial recommendations, not a report of a customer incident.