Diesel is not the same as gasoline. Gasoline (via its vapor) is flammable, while diesel is combustible. Similar to gasoline, it is the vapor that ends up catching fire rather than the liquid itself. Diesel tends to burn slower than gasoline, so it doesn't exactly explode, but is much more difficult to put out.

Can you start a fire with diesel?

In its vapor form, diesel is very dangerous and can catch fire (or explode) easily in the presence of an accelerant such as fan air or oxygen. Diesel is a stable liquid at normal outdoor temperatures. ... The vaporization rate increases as the temperature increases. Diesel vapors can ignite and explode when mixed with air.

Does diesel catch fire easily?

If you toss a lit match into a puddle of diesel fuel, it'll go out. That's because diesel is much less flammable than gasoline. In a car, it takes intense pressure or sustained flame to ignite diesel.