When To Replace A Toyota Fuel Filter

The life of your Toyota's fuel filter depends on which model you have and how old it is. Most newer Toyota's have fuel filters that are designed to last the life of the car. Older Toyota's have filters that should be changed about every 30K miles, or 2 years. The only way to know for sure is to look it up in the owner's manual for your vehicle. If you think that your fuel filter may be getting clogged, you came to the right place. We'll help you confirm it.

Signs Of A Clogged Fuel Filter

Filter

Image Credit: YotaTech

A bad fuel filter affects your engine's performance. When a fuel filter is too clogged, your engine won't get enough fuel or any fuel at all. When this happens, you'll notice some of the following signs:

  • Reduced engine power
  • Engine stumbling when accelerating
  • Misfiring
  • Fuel leak at the filter

To confirm that your fuel filter is bad, you can do one of these two things:

  1. Perform a fuel pressure test
  2. Give the fuel filter a visual inspection

Checking The Fuel Pressure

Pressure

If you don't have a fuel pressure tester, you can rent one from AutoZone or another store. Here's how you can check the fuel pressure on your Toyota:

A Few Things To Do First

There are a few things to do first before performing a fuel pressure test:

  1. Make sure that there is gas in the gas tank. Don't trust the gas gauge.
  2. Make sure that the fuel pump works. Remove the gas cap and turn on the ignition. Listen for the fuel pump at the fuel fill opening. There should be a whirring/humming noise. If there isn't noise, that means the fuel pump is either broken or not getting power. You can't do a fuel pressure test with a malfunctioning fuel pump.

Performing A Fuel Pressure Test

Take the following steps to perform a fuel pressure test:

  1. Make sure that the engine is off, and cold.
  2. Pop the hood.
  3. Find and remove the Schrader valve cap on the fuel rail. On some cars, it may be hidden under a fuel rail cover or the engine cover.
  4. Find the appropriate fuel pressure tester fitting. Attach it to the tester, and then thread it into the Schrader valve.
  5. Turn the ignition to "on". Don't start the engine.
  6. Check the psi reading on the fuel pressure tester gauge. Take some time to watch for a psi drop. This indicates a leak in the system. If the reading remains the same after 5 or 10 minutes, the fuel system has adequate pressure.
  7. Start your engine, and then let it idle. Watch the psi reading to see if it remains steady.
  8. Once the engine is warmed up, give it a slow rev. The pressure should rise with the RPM. If it's not, then it's possible that the fuel filter is clogged or there's a leak somewhere in the system.

Interpreting The Fuel Pressure Readings

Check your owner's manual for the recommended psi reading. Compare your readings against the recommended reading.

  • Is there zero fuel pressure? The fuel pump is dead or not getting power.
  • Is the fuel pressure low? The fuel filter could be clogged. This could also mean a failing fuel pump.
  • Is the fuel pressure normal, and reacting normally? The fuel filter seems fine.
  • Is the fuel pressure high? There could be a problem with the return line, fuel pump driver module, or powertrain control module.

Checking The Fuel Filter

Check filter

Image Credit: TacomaWorld

If you don't want to do a fuel pressure test (or if you get incomplete results), you can visually inspect the fuel filter. To do this:

  1. Make sure that the engine is off.
  2. Put an oil drain pan or a bowl underneath the fuel filter to catch any fuel that will leak out.
  3. Scoot underneath your Toyota and then remove the fuel filter. You need a fuel filter removal tool to do this.
  4. With the fuel filter in your hands, take it apart with the fuel filter removal tool.
  5. Pour the fuel out of the filter and into the oil pan or bowl. Observe the color of the fuel.
    1. If the fuel is a rusty color (brownish, orangeish), then the fuel is dirty. This could mean one of these few things:
      1. The fuel filter is clogged.
      2. A component within the fuel filter is rusted.
      3. The fuel was bad to begin with. In this case, you may want to check the fuel tank to see if the fuel in it is dirty, too.
    2. If no fuel comes out of the filter, there's a clog in the line somewhere.
  6. If your fuel filter has a top cap, remove the cap and then take the paper filter out. See if it's dirty enough to warrant replacing.

When In Doubt, Replace The Fuel Filter

If you're not sure if the fuel filter is bad, we recommend replacing it anyway. Replacement fuel filters are pretty inexpensive. In fact, you can get a genuine OEM fuel filter at wholesale pricing if you order one from us.

Written by Jason Lancaster