Have scan code P300, P0304, P0305, P0306, P0171.

2006 FORD FUSION
130,000 MILES
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ROBERT54
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I have check for vaccum leaks none,change spark plugs, and replaced coils. Still get the same engine code, the check engine light came back on after cleared. The engine temp is normal.
Oct 15, 2012 at 5:45 PM
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KHLOW2008
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The system is running lean with random misfres and cylinders 4, 5 and 6 seems to be badly affected.

Which engine do you have?
Oct 15, 2012 at 6:53 PM
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ROBERT54
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My engine is V6 3.0L.
Oct 16, 2012 at 6:15 AM
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KHLOW2008
  • ✓ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
Check the PCV valve and its hose for damage and vacuum leakages.The hose may be wrapped in heat protective covering which makes it a little harder to find damage.Your misfires are all on one side of the engine, I would look for something isolated to that bank

Heres a couple guides to check out, they will help you figure it out

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

https://www.2carpros.com/articles/engine-misfires-or-runs-rough
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Oct 16, 2012 at 7:41 AM
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