Paul Rosche’s naturally-aspirated V12 that powered the McLaren F1 was, and still is, a masterpiece. In fact, it may be the greatest road car engine ever made (until Cosworth’s new V12 in Gordon Murray’s follow up to the F1 arrives). However, it does have one minor flaw — it won’t run on diesel.

During a recent drive, racing driver François Perrodo needed to fill the tank of a McLaren F1 GTR and grabbed a nozzle without looking at what it was. The color of the nozzle was also similar to the normal 91 octane petrol that he’s used to, so at a quick glance, he thought he had the right one. However, instead of it being 91 octane unleaded, he accidentally filled it up with diesel. Oops.

For those that don’t know, the S70/2 engine that powers the McLaren F1 GTR is one of the most finely tuned, high-strung engines ever made. It’s a 6.1 liter atmospheric V12 that makes 627 horsepower and revs to 7,500 rpm, making the most incredible noise on the way there. It’s an engine from the gods. So you can imagine that filling it up with diesel fuel is tantamount to drinking bleach.

Thankfully, the only thing that happened was the car wouldn’t start. In fact, Perrodo’s pride was hurt more than the car’s engine. In a couple of Instagram posts, he tells the story of his mishap, owns up to his mistake, and discusses what happened afterward. Rather than thousands of dollars in repairs, as some journalists suggested, it just needed to have its tank drained and refilled to get back on the road. Goes to show that Rosche’s engine is tougher than it looks.

So just make sure, when you fill your tank in a high-priced exotic, make sure you fill it with the proper fuel, especially when you’re with your friends, or you’re gonna look like a proper idiot. But if you do mess up, take it on the chin like Perrodo.