Wrong Fuel FAQs – Petrol in Diesel, Diesel in Petrol & AdBlue
Put the wrong fuel in your car? The safest first step is simple: don’t start the engine. Below are the most common questions we get – what to do immediately, what happens if you started it, how the drain process works, typical timeframes, and pricing.
If it just happened, don’t turn the key again – call first.
First steps after misfuelling
If you’ve put the wrong fuel in, what you do in the next 60 seconds matters. Start here.
Petrol in a diesel engine
Petrol in diesel is common. The biggest risk is starting the engine and circulating the wrong fuel.
Diesel in a petrol engine
Diesel in petrol usually causes poor running or no-start. A drain and flush is often the quickest fix.
AdBlue misfuelling
AdBlue in the diesel tank is urgent. Don’t start the engine – get advice immediately.
Mobile fuel drain process & timing
How the drain works, how long it takes, and what to expect after we finish.
Pricing & what affects cost
Transparent pricing. We confirm the total before starting any work.
Vehicles we work on & service coverage
Cars, utes, 4WDs, vans and fleets – we come to you.
What to have ready when you call
A few details helps us quote fast and get you sorted quicker.
What should I do immediately after putting the wrong fuel in?
Don’t start the engine. Turn the ignition off and avoid cycling it. Leave the vehicle parked safely and call us with your vehicle type, what fuel went in, and whether it was started.
Can a small amount of wrong fuel cause damage?
Sometimes, yes. It depends on the vehicle, fuel type, and whether the engine was run. If you’re unsure, don’t start it – get advice first.
What happens if I started the engine after misfuelling?
Starting can circulate the wrong fuel through the system, which can increase the work required. Tell us how long it ran and whether it was driven – we can still help.
What if I’m stuck at a servo and can’t move the car?
Leave it parked safely and don’t start it. Let staff know you can’t move it yet. Call us with your exact location and what happened.
Can I dilute the wrong fuel by topping up the correct fuel?
It’s risky. Topping up can still leave wrong fuel circulating once started. Best practice is to avoid starting and have it assessed/drained properly.
What should I do if I put petrol in my diesel car?
Don’t start it. Petrol reduces lubrication in diesel systems and can cause damage if circulated. A drain and flush early is usually the best outcome.
How much petrol in diesel is “too much”?
There’s no one number for every vehicle. The more petrol added and the more it was run, the higher the risk. If it hasn’t been started, draining early is usually the cleanest fix.
Will petrol in diesel damage injectors or the fuel pump?
It can if it’s circulated. That’s why not starting the engine is important – early action reduces risk.
Will diesel in a petrol engine cause permanent damage?
Don’t start it (or switch it off safely). Diesel can foul components and cause no-start. A drain and flush is often the quickest fix.
Can you help with AdBlue in the diesel tank?
Yes – and it’s urgent. Don’t start the engine. Call us immediately so we can guide you and organise the correct process.
What if diesel was added to the AdBlue tank instead?
That’s a different issue and needs the DEF/AdBlue system assessed. Don’t run the vehicle until you’ve had advice – call us and we’ll guide the next steps.
What is a wrong fuel drain and how does it work?
We remove contaminated fuel from the tank and, where required, flush lines and prime/bleed the system so it can run safely again. Steps vary by vehicle and what happened.
How long does a mobile fuel drain usually take?
Most jobs are completed within 15-30 minutes, depending on tank size, access, contamination amount, and whether the engine was started.
Will the car start after the fuel is drained and flushed?
In many cases, yes — especially if it wasn’t started. If it was run/driven, extra steps may be required. We’ll explain what to expect before we begin.
How much does a wrong fuel drain typically cost?
Most standard call-outs are typically $400–$550. Price can vary if the engine was started, the tank is large, access is difficult, or extra steps are required. We confirm the price before starting.
What can increase the cost or time required?
Engine started/driven, large tanks (vans/4WDs), difficult access, higher contamination volume, and extra steps like filters/priming/diagnostics can affect cost and time.
Do you work on vans, 4WDs and fleet vehicles?
Yes. Fleet and larger vehicles are common – we’ll just need vehicle type and what fuel was added so we can quote accurately.
Do you come to homes, workplaces and roadside locations?
Yes – we’re mobile and come to you. Share your exact location and any access notes so we can respond quickly.
What information should I have ready when I call?
Vehicle make/model, petrol or diesel, what fuel was added and roughly how much, whether it was started/driven, and your exact location.
Can you still help if the engine has already been started?
Yes. Tell us what happened and we’ll advise the safest next steps and what the process will likely involve.
Do you remove contaminated fuel safely and legally?
Yes — contaminated fuel is handled and disposed of responsibly as part of the service.
Also servicing nearby areas
Based in Brisbane? No worries – we also service Logan and the Gold Coast.
Not sure which area you’re in? Call 1300 369 215 and we’ll confirm.
Wrong Fuel Company provides mobile wrong fuel services across South East Queensland, including Logan, Brisbane and the Gold Coast & Northern NSW.
Pricing & What Affects Cost