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What Problems Can A Loose Gas Cap Cause?

The gas cap, otherwise known as the fuel filler cap, is an important but simple part found on most vehicles on the road. The gas cap makes a reliable seal that stops dirt, dust, and debris from getting into the gas tank.

It can play a huge role in the emissions system that turns harmful fuel vapors into harmless elements.

Since the gas cap is removed and replaced each time you put gas in your vehicle, it may need to be replaced in time. A loose gas cap can cause problems ranging from an annoying gas smell to a more serious engine leak.

What problems can a loose gas cap cause? Keep reading to find out.

Signs You Should Check Your Gas Cap

Gas Cap on a car in what problems can a loose gas cap cause

Typically, there are a few signs that can indicate a faulty gas cap. Here’s what to look for.

Loose Gas Cap

Struggling to tighten your gas cap is a common sign of a broken gas cap. Often, gas caps are made so that they will click once to indicate they are tightened. If you do not hear a clicking noise despite tightening the cap as usual or if you hear a click but the cap pops back loose, you may need to replace your gas cap.

Smell of Gasoline

Damage or wear and tear to the gas cap may cause vapors from the gas tank to leak, resulting in the inside of your car smelling like gasoline.

Check Engine Light

The most common reason for a check engine light is a loose gas cap. Since the check engine light comes on for many reasons, it is best to scan the car for trouble codes. If your check engine light is on, you cannot pass an emissions test.

How to Replace Your Gas Cap

hand holding a Gas Cap Tool in what problems can a loose gas cap cause

The exact steps of removing and installing a gas cap will vary depending on your vehicle’s make, model, and year.

For Standard Cars

To remove, twist the gas cap off. Remove the leash of the gas cap. To replace, unwind the leash of your new gas cap. Connect the locking peg at the end of the leash to the hole in the fuel tank door until it is locked in place.

Twist the gas cap on. It should fit just as your old one did.

For Quick-On Locking and Pressure Release Gas Caps

To remove, insert the key to the gas cap on the cap’s handle. Use they key to rotate the cap to the left. Grab the cap and rotate it a bit further to the left. Remove the key; the gas cap should come right off.

To replace, rotate the cap to the right, inserting it into the fuel tank opening. Test the cap by turning it to the left; if it bulges, it is loose.

For Metal Push-On Locking Gas Caps

What problems can a loose gas cap cause? When a gas cap is broken or improperly sealed, fuel vapors escape from the gas tank. This will cause a decrease in your fuel economy.

If the gas cap is loose, it could cost you up to 30 extra gallons of gas in a year. That’s huge!  A gas cap that is not sealed correctly may cause an engine leak. If the gas cap is missing altogether, you are at risk of catching your car o​​n fire each time you drive.


Car Gas Cap in what problems can a loose gas cap cause

What problems can a loose gas cap cause? If you think your gas cap is loose, it is important that you have it inspected by a professional to determine if you should replace the gas cap.

While the smell of gas may be unpleasant, a loose case cap can have costly consequences if not addressed.