Vehicle has misfiring and O2 codes.

2004 GMC SAVANA
23,237 MILES
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LYNDON GORDON
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My 2004 GMC Savana V6 3500 VIN# 1GDJG1U141140461, misfire when it warms up. it stifles during acceleration. Small explosions can be heard in the exhaust system when the un-burnt gas ignites, while laboring to accelerate. What can be the problem? Vehicle has misfiring and O2 codes.
Dec 13, 2011 at 9:33 PM
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ASEMASTER6371
  • ASE Certified Mechanic
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  • ASE Certified Mechanic
repair the miss fires first and the o2 code may go away.

i would start with plugs, wires fuel and air filter.

Roy
Dec 13, 2011 at 9:49 PM
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LYNDON GORDON
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Vehicle has new plugs and wires, runs good when cold. It starts to shake when it reaches normal operating temperature. To prevent misfiring I would turn it off at stop lights and restart it when light turns green. If I allow it to idle too long, it will start to misfire and shake.
Dec 14, 2011 at 2:02 AM
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ASEMASTER6371
  • ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
other possibles are injectors, vacuum leaks and coil failure.

Roy
Dec 14, 2011 at 2:05 AM
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