1996 GMC Suburban Code PO306

1996 GMC SUBURBAN
205,000 MILES • V8 • 2WD • AUTOMATIC
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JON HALE #1
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I've replaced the valve stem seals, plugs, wires, cap, rotor, CPI fuel injector unit and it still runs rough when it's cold and idling. Any ideas?

Thanks.
Mar 6, 2010 at 5:26 PM
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RASMATAZ
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Engine running rough or misfiring can be cause by the following:

1.Defective spark plug.
2.Inadequate spark/coil,defective spark plug wire.
3.Lack of compression
4.False air leakage.
5.Faulty fuel injectors.
6.Insufficient fuel pressure.
7.Contaminated fuel.
8.EGR valve that is leaking.
9.Oxygen sensors.
Mar 7, 2010 at 4:48 AM