How To Clear A Clogged Fuel Line

A fuel line regulates the flow of fuel. Occasionally, a fuel line can get clogged up with rust and/or deposits from the gas tank.

If you’re dealing with a clogged fuel line, it’s important to clear it out right away because a clogged fuel line keeps the engine from getting enough fuel. The fuel flow gets backed up and most of it goes back into the fuel tank instead of going forward into the engine. As a result, your engine will have trouble starting or staying on. In some cases, the fuel may leak and come into contact with an ignition source, causing smoke or even a fire.


Wondering if you have a blocked fuel line? Check for the following tell tale signs:

  • Difficulty starting the car
  • Decreasing power
  • Smoke coming from under the hood
  • A strong fuel odor

Rule Out Other Issues First

A clogged fuel line isn’t a common problem, so it’s a good idea to rule out more common issues, such as a dirty fuel filter or a failing fuel pump, first. Even if your car is diagnosed with a clogged fuel line, there’s still a chance that it’s not the actual problem. Sometimes intermittent fuel pump failures can appear as a clogged fuel line in the diagnostic process.

Fuel Line

Let’s go over the most common symptoms of a blocked fuel filter and a failing fuel pump so you can determine if you’re dealing with one of those problems instead of a clogged fuel line.

Symptoms of a Dirty Fuel Filter

  • The engine losing power or cutting out while driving uphill
  • Hesitation on acceleration
  • Stalling engine
  • Different performances at different speeds

Basically, the symptoms of a blocked fuel filter are similar to those of a clogged fuel line. So the best thing to do here is to give your fuel filter the eyeball test, meaning inspecting it physically to see if it’s dirty.

Symptoms of a Failing Fuel Pump

  • A buzzing or humming sound coming from the fuel tank area
  • Slow and/or jerky acceleration
  • Decreased fuel efficiency
  • The engine choking after running for a while

[Read more about failing fuel pumps here]

If you've determined that you are, in fact, dealing with a blocked fuel line, put on gloves, safety goggles, and a long-sleeved shirt so you can get to work clearing the fuel line!

Clearing a Clogged Fuel Line in 10 Steps

  1. Turn your vehicle off.
  2. Disconnect the battery.
  3. Remove the fuel pump fuse from the fuse box.
  4. Turn on the engine and keep it running until the pressure in the fuel line is reduced.
  5. Turn off the engine.
  6. Disconnect the fuel line from the filter and the tank/pump.
  7. Shoot some air through the line with compressed air until the line is open again.
  8. Reattach the fuel line to the filter and the tank/pump.
  9. Put the fuel pump fuse back in the fuse box.
  10. Start the engine to increase the pressure in the fuel line. Be sure to listen for any issues.