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Every 4 years or 60,000 miles the fuel filter should be replaced. Like most maintenance items, ignoring or skipping the service may result in a higher total cost of ownership. How? If the fuel filter element degrades, it can allow chunks of the filtering material and/or dirt that is suspended in the fuel to pass downstream to the injectors. That can result in clogged injectors with poor spray patterns. Poor spray patterns can cause incomplete ignition, which can result in lower fuel economy. Also, raw fuel is bad for oxygen sensors and catalytic converters. Partially clogged filters can cause the fuel pump to work harder, hastening the pump's demise. Filters that become fully clogged have been known to cause an engine to simply stop. Any of these problems will cost more to fix than a fuel filter service. My last Bosch filter was $37, so it's not the type of service that will break the bank.

Like most jobs, tools are required. This job doesn't require anything special, but tools are needed - especially the pan. A fuel filter holds about a pint of gasoline. Better in a pan than on my garage floor.

The filter is underneath the car, in the rear, so the car must be elevated. A full lift isn't required, but there must be enough room to slide underneath on a creeper.

The fuel filter is underneath a cover. The fuel pump cover is removed by unscrewing three nuts. The nuts can be reached through the access holes in the cover.


The filter is to the right and just forward of the diff

Nut on the right

Nut on the left

Access holes


Using the access holes, the nuts and cover were removed.

With the cover removed, the fuel pump and filter are exposed. The filter has four fittings. The hoses under pressure have clamps. My filter has been replaced a number of times and uses screw type hose clamps. The OE clamps were crimp fittings.

Before I touch the hose clamps, I use vice grips to clamp the fuel lines shut. Without the clamps, fuel will run from the lines. After clamping the lines, the pan is slid under the filter. Even though the lines are clamped with vice grips, some fuel will escape.

With the pan in place and lines clamped, I looked at the filter, noting the writing on it and where the lines went. My new filter was a Bosch unit. It has the same writing as the filter that was removed. The key is to put the hoses back in their original spots on the new filter. At that point, the hoses were removed. After the hoses were removed, the clamp that holds the filter in place was loosened.


Bosch filter

Four fittings

Each fitting is clearly marked

 

The old filter slid out and was placed in the pan. The new filter is slid in. The hoses, clamps, and cover were reinstalled in their original positions.

Notes: Before replacing the cover, I pressurized the system (turned the key to the second position). This made it easy to confirm there were no leaks. The contents of the pan show there was a fair amount of fuel in the filter.

This web page is for entertainment value only. I do not recommend placing cars on ramps, crawling under cars, disconnecting fuel lines, replacing fuel filters or handling gasoline. I also do not guarantee the accuracy of these instructions or pictures and highly recommend that everyone use the services of a qualified mechanic to perform ALL MAINTENANCE, REPAIRS, & VEHICLE SERVICE.

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