Car Repair: How to Replace a Gas Filter

Gas filters on cars come n many shapes and sizes. In spite of this, gas filters are located in two general areas of the car. Most cars have two gas filters. One is located in the fuel tank. The other is an in-line gas filter. Acquainting yourself with the precise location of the gas filters on your car is important if you plan to change them yourself.

In-line gas filters are placed along the fuel line.

To find an in-line filter, start at the fuel tank and begin to work you way toward the engine. You are looking for a plastic or metal canister. It will be between 1 and 3 inches long and between 1/2 and 3 inches in diameter. The fuel line will attach to it on each end.

Most filters need to be changed due to moisture and debris from the fuel tank.

Moisture can get into the gas tank from three sources. during the warming and cooling of the tank, condensation may form on the inside of the tank and run down into the gasoline. The fuel has additives designed to absorb much this moisture to reduce the problems that it can cause. When the fill cap is removed during a rain, some of the water can end up in the tank. Finally, water can sometimes get into the enormous tanks at the filling station. It is pumped along with the fuel into your gas tank. The filter in the gas tank is not designed to stop this moisture, but the in-line gas filter is.

Get a small open container that is resistant to gasoline.

You will need this to catch any gas that drains from the fuel line while the filter is being changed. Removing the filter will require an open end wrench for each end of the gas filter. Using two wrenches will keep you from twisting the fuel line and risking doing damage to it. If you do not have two wrenches that are the correct size, you may be able substitute vice grips, channel locks, or an adjustable wrench like a crescent wrench in place of one the end wrenches. Some filters, especially on older vehicles, clamp into place with a short piece of rubber hose on each end. Pliers or a screw driver will be needed to loosen and tighten the clamps.

Some models have special fittings to hold the filter into place.

To release this fitting, a special tool has been created. This tool is somewhat expensive. If you are careful, you can get to release with a pair of needle nose pliers and a screwdriver. Many these fittings have a small plastic keeper that needs to be removed before it will release. Be sure to push this keeper back into place at the end of the process when the new filter is installed. These filters usually have a short piece of tubing attached that has part of the special fitting bonded to it. The keeper will not slip back into its slot if you do not get the fitting pushed all of the way into its place. If you are intimidated by this hardware, take it to a mechanic. almost any mechanic will have no problem with it.

Changing the filter inside the fuel tank is usually not necessary unless you are replacing the fuel pump.

Siphon or pump all of the fuel from the tank. Carefully loosen the clamp that holds the tank to the cars fuel spout. Begin to loosen the straps that hold the fuel tank in place. When the tank is almost loose, tilt it so that you can unplug the wires that provide power to the fuel pump. The empty tank will not weigh but a few pounds and is not difficult to lift and move. Lower it to the ground.

Open the lock ring that holds the fuel pump in place and pull the pump from the tank.

You will see a tube running from the pump downward into the gas tank. It will have a small boot filter on the end of it. Slide the filter from the tube and install the new one. Return the fuel pump to the tank. Reverse the removal process to put everything back into place. Be sure to plug in the fuel pump before fully tightening the gas tank straps. A new fuel pump will have a new filter already attached. Pour the gasoline back into the tank. Your car should be ready to drive.