2003 Cadillac CTS misfire

2003 CADILLAC CTS
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CADDYDEVILLE
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Engine Performance problem
2003 Cadillac CTS 6 cyl Automatic 122000 miles

i have codes of po300,po302,po303.po305 car runs but sounds like its tapping
Jul 24, 2009 at 7:37 AM
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RASMATAZ
  • ✓Experienced Mechanic
  • 75,988 POSTS
Misfires can be caused by worn or fouled spark plugs, a weak spark (weak coil, bad spark plug wire), loss of compression, vacuum leaks, anything that causes an unusually lean fuel mixture (lean misfire), an EGR valve that is stuck open, dirty fuel injectors, low fuel pressure, or even bad fuel.
Jul 24, 2009 at 8:42 AM
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