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How to use Seafoam to clean up your engine

by Contributor

Seafoam is a great way to de-gunk your engine. Seafoam is a complete fuel system cleaner. It can reduce carbon build up, reduce ping, a rough idle, improve gas mileage and clean out your fuel system. This can save gas and give you more miles to the gallon. If you're thinking about cleaning your fuel system, check this out.

Step 1

Go to your local auto part store and pick up a can of Seafoam.

Step 2

After warming up your engine. Keep the engine running at a high idle and locate either the PCV valve or the brake booster vacuum line. Choose which one you'd like to use and disconnect it.

Step 3

Using the PCV valve pour about 1/3 of the can in. If you use the vacuum line, pour 1/3 of the can into a container and then use the vacuum line to suck it out of the cup. If the engine stalls before you get it in, try sucking the fluid in slower. You may want to cover part of the line with a finger. When you have 1/3 of the can in the car turn off the engine.

Step 4

Pour 1/3 can of Seafoam into your gas tank.

Step 5

Pour 1/3 can of Seafoam into your oil via the crankcase.

Step 6

Wait about 5-15 minutes.

Step 7

Start the engine back up. You may need to give it a little gas to keep it from stalling. Expect to see a fair amount of smoke, so you'll want good ventilation. Do this at night or away from people to avoid bugging the neighbors. Idle your car for a few minutes and then take it for a drive.

Step 8

Expect to change your oil in the next few hundred miles. Seafoam is not for long term use in the oil.

Congratulations, now your car should run better, save gas, and run more efficiently. Your fuel system should be nice and clean of carbon build up.


  • Some argue that sucking through the brake booster may cause potentially damaging hydro locking.
  • Do this in a well ventilated area.

Items you will need

  • Can of Seafoam
  • Shallow container

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