5 Common reasons for the smell of gas inside a car axleaddict electricity billy elliot backing track


"What causes the smell of gas inside a car?" is a question I hear almost every day. A gas leak might make sense as the most likely cause; but more often than not, the cause is unburnt gasses leaking from the engine or exhaust, in places where most people would never even think of looking. Here are five possibilities worth checking out. 1. The Oil Cap’s O-Ring or Gasket

A very common place for a fume leak from the engine, which is very easy to overlook, the O-ring or gasket under the oil cap. I find this quite often and it’s only a $5 repair. It’s a very easy diagnosis, taking about 15 seconds, to determine if this could possibly be the source of your fuel smell. Here’s what to check;

• Open the hood and look at the area around the oil cap, if you notice oil and debris collecting on the valve cover just below the oil cap, most likely the o-ring is worn out and is leaking, causing fumes from the engine, which "smell like gas” to leak out and be drawn into the HVAC (Heating Ventilation Air Conditioning) fresh air intake located directly below the windshield.

• Check the oil cap for cracks, if you see any cracks, replace the entire oil cap. It may be a little difficult to get the right one because there are so many different sizes. If your local auto parts store doesn’t have one you could try the dealership or salvage yard.

What about oil leaks? Do you have used motor oil leaking out of the engine by an old gasket? Is it weeping down the side of the motor? Maybe it’s dripping onto the hot exhaust system? Used motor oil from inside the engine has unburnt fuel mixed into it, so if it’s leaking out of the motor and onto hot components, it could be the source of your fuel smell. What to check;

• Valve cover gaskets are notorious for leaks. They sit at the top of the engine and absorb the most heat, which causes them to fail sooner then most gaskets. Also they sit right above the exhaust manifold which is the hottest section of the exhaust system. Inspect this area closely for any drips going down the back side of the engine.

• Look for any smoke coming off the engine when it’s hot. Smoke coming off a hot engine is a good sign there is an underlying oil leak that you cannot see. To find a small leak, you may need to bring the car to your local mechanic. Have them clean the oil off the engine and then add a fluorescent dye to the oil. This dye will glow green when a special UV flashlight is used to inspect the leak area.

Exhaust leaks are another common fuel smell that gets drawn into the passengers compartment via the HVAC fresh air intake, especially if the exhaust leak is close to the engine and before the catalytic converter. An exhaust leak before the catalytic converter can have a pungent fuel smell, because the exhaust includes a lot of unburnt gasses before the converter cleans them out of the system on the way to the tail pipe.

• Listen for a ticking noise when accelerating. If the exhaust leak is close to the engine, the exhaust leak will make a loud ticking noise like someone tapping on a pie plate, if you hear this type of noise on acceleration, have your mechanic check your exhaust manifold for leaks.

• If you think you may have an exhaust leak but are not sure, try placing a doubled-up towel over the tailpipe and put your hand over the towel to stop the exhaust from exiting the tailpipe. If you don’t feel the pressure building up at the towel, most likely you have a leak somewhere in the exhaust. If you have dual exhaust pipes, you may need an assistant to help block the other tail pipe at the same time.