sunbird misfires

1992 PONTIAC SUNBIRD
90,000 MILES
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T.O.NERO
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its a 1992 sunbird gt 3.1L it has been misfiring for the past few months i have changed the fuel filter replaced most of the fuel line new spark plugs and wires a new EGR with new mufflers ran injector cleaner non of this did anything any ideas?
Sep 16, 2012 at 4:01 PM
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SATURNTECH9
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When does it miss?How bad does it miss?
Sep 16, 2012 at 4:19 PM
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T.O.NERO
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its starting to do it at an idle and it does it every turn of the engine if i floor it or just does it randomly it also has a knocking in the engine now
Sep 16, 2012 at 9:57 PM
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SATURNTECH9
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At idle pull off a spark plug wire and put it back on do that with all the wires and see if the rpms drop on each wire you pull off.Becarefull not to shock yourself let me know what you find.
Sep 16, 2012 at 11:30 PM
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T.O.NERO
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Alright I did what you said and I found out that it's one of the 3 in the back of the engine but I can't figure out what one cuz it doesn't misfire all the time
Sep 24, 2012 at 6:58 PM
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SATURNTECH9
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So you can't narrow it down to which cylinder?
Sep 24, 2012 at 10:53 PM
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T.O.NERO
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Ya I can't I know it's one of the 3 back ones not sure what one tho
Sep 24, 2012 at 10:54 PM
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SATURNTECH9
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Cant you see or hear the spark shorting to ground anywhere?
Sep 24, 2012 at 11:42 PM