Author Archives: kevin

Petrol In a Diesel Car: What’s So Bad About It?

You would not be the first or last person to accidentally fire up the wrong fuel pump and start feeding petrol into your diesel engine. If you have ever been in this situation, the chances are you vowed never to make the same mistake again.

It’s a well-documented “no-no”, but what exactly is it that makes mixing up engine juice so bad?

What’s the Difference Between a Petrol and Diesel Engine?

Diesel engines have grown extremely popular across Europe and Australia for their reduced CO2 emissions and improved driving performance. Diesel engines are more powerful and get better mileage from a full tank, compensating for the higher initial cost. In America, diesel engines haven’t taken off in quite the same way because of the comparably low cost of petrol, but the appeal of a smoother, more efficient drive is slowly tempting more buyers.

The mechanisms and technology behind the two types of engines are also different. Petrol engines ignite via a spark and the pressure from the gas gets the machine going, whereas diesel engines compress air, raising the temperature until it ignites spontaneously.

Why Is It So Important to Use the Correct Fuel?

Because of the contrasting chemical make-up of petrol and fuel, they do completely different things when pumped into your car. Diesel is designed to act as a lubricant for the modern technology built into these new and proved engines to keep emissions low and power high, but the metallic elements of petrol do the opposite. As petrol runs through the pipes it creates friction and puts serious strain on the inner workings of the machine.

Think of an engine as your car’s heart. If diesel is the blood you need, injecting petrol is like injecting oil into your veins. Friction and blockage are two things you certainly don’t want in your vehicle’s cardiac system.

What Can Go Wrong?

When petrol enters a diesel car, various things can go wrong depending on how quickly you realize the error. The damage can range from simply ruining your day and wasting your time, to an eyewatering mechanic’s bill worth more than the car itself.

The best-case scenario is that you realize very quickly after filling less than 5% of your engine, in which case you call your mechanic or recovery service who can drain the engine with little harm done. If you have filled substantially more but catch the mistake before you switch on the engine, you could still get away relatively lightly, but with a slightly higher bill.

The real trouble begins as soon as you start your car. DO NOT start your car if you notice the error on time. As the engine runs, the offending petrol coats the pipes and gets sucked into all the places it doesn’t belong. The more you drive, the worse the friction becomes, the more the petrol clogs your engine, and the more irreparable the damage becomes. Your car eventually goes into vehicular cardiac arrest.

When this happens, the bill could be astronomical, with several specialty parts likely to need replacing.

The moral of the story is, double and triple check the label on the pump before filling up your diesel engine; those few extra seconds you spend could wind up saving you thousands of dollars.