How to Clean Your Fuel System Before Replacing Your Fuel Pump

Did you know that there are millions of particles floating around in your fuel tank? Most of these contaminants are harmless enough by themselves, but they can cause all sorts of fuel system problems over time. For example:

  • Clogged fuel injectors
  • Clogged fuel filters
  • Corroded fuel system components (namely, the fuel pump itself)
  • Premature fuel pump failure, due to clogs and corrosion

SO, before you replace a fuel pump, it's a good idea to run some cleaner thru your fuel system.

Where Do All These Contaminants Come From?

Fuel Nozzle
9 times out of 10, fuel contaminants come from your local gas station


Fuel system contamination can come from a variety of sources:

  • Ambient dust and grit in the air that gets inside the tank during fill-ups
  • Water from the air (in the form of humidity) that can carry dirt into your system every time you fill-up
  • Corrosion of the fuel system itself, which creates loose small bits of rust, rubber, and plastic

Usually, however, most of the contamination is from none of the above. Instead, it's from your local gas station. Underground tanks store fuel, and these tanks inevitably collect dirt, grime, water, etc. The older the gas tank, the worse the contamination is likely to be.

How A Dirty Fuel System Costs You Money

Dirty fuel costs you money in two main ways:

  1. It reduces your vehicle's fuel economy, meaning you waste money buying more gas than you should
  2. It reduces the lifespan of various parts of your fuel system, causing you to buy replacement parts sooner than you should

A clogged fuel filter or injector will also reduce your car's performance, causing slow acceleration, rough idle, and stalling. In extreme cases, these clogs can lead to more serious engine problems (only this isn't too common).

For these reasons, periodic fuel system cleaning is a good idea. A bottle of fuel system cleaner is a good idea every year or two, not only because it can help injectors stay clean, but also because it can bond with water in your fuel system and help burn it off. Water is a problem because it facilitates corrosion.

Additionally, it's important to replace your vehicle's fuel filter whenever the manufacturer recommends doing so (if not sooner).

Clean Your Fuel Tank Before Replacing Your Fuel Pump

If you're planning on replacing your fuel pump, it might be a good time to clean your fuel tank, too.

Old gas pump
Remember, the older the gas station, the older the underground storage tanks. Image copyright Daryl Mitchell.


You can bring your car to a local radiator shop and have them steam clean your tank. Doing so will restore your tank to the brand new condition it was in right when it rolled off the assembly line.

You can also go the DIY route, which is obviously more affordable. Here's how:

  1. Remove the fuel tank from your car.
  2. Swish it around to help the fuel collect the debris stuck on the walls of the tank.
  3. Remove the old fuel pump and toss it out.
  4. Drain the fuel from the tank. Be sure to filter it and store it in an approved container or fuel caddy.
  5. Using soap and water, wipe down the outside of the fuel tank to remove any road debris and/or rust.
  6. Clean the inside of the tank with soap and water. For best results, use pressurized water.
  7. Wipe down the inside of the tank with a lint-free towel until completely clean and dry. You can also dry it out with compressed air. Whatever you do, it's important that the tank is 100% dry before putting the fuel back in.
  8. Pour the fuel back into the tank.
  9. Install the new fuel pump.
  10. Put the tank back on the car.

Once the fuel tank is clean, remember to replace your fuel pump components with high quality parts, like those from Auteria. High quality parts last longer, and keep your car running its best.