1999 Cadillac Escalade

1999 CADILLAC ESCALADE
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MPEAT1
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Engine Performance problem
1999 Cadillac Escalade V8 Four Wheel Drive Automatic

why does my escalade shake and miss fire when i go uphill while towing a trailer and most recently on highway with trailer @ 60 mph. in september i replaced plugs, wires, cap, rotor, and #4 injector. what am i missing i cant figure it out?
Apr 7, 2010 at 9:21 AM
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FACTORYJACK
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Was the tune meant to address this misfire? Did it start misfiring after the tune?
Apr 14, 2010 at 10:02 PM
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MPEAT1
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[quote:9d010bb504="gstacey"]Was the tune meant to address this misfire? Did it start misfiring after the tune?[/quote:9d010bb504]

It didn't change. I even replacedthe #4 injector because that was what the code said was the cylinder that was miss firing the most. After running the vehicle with computer hooked up other cylinders showed misfires but not enough to set code.
Apr 15, 2010 at 10:12 AM
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FACTORYJACK
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If it only misfires under extreme loads like towing, I would suspect ignition. If it is misfiring on all cylinders it could be lower than required fuel pressure, or a restricted exhaust. Another check would be compression, and leakdown. Can you get this misfire during a torque brake?
Apr 15, 2010 at 11:49 PM
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MPEAT1
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[quote:c669ff0190="gstacey"]If it only misfires under extreme loads like towing, I would suspect ignition. If it is misfiring on all cylinders it could be lower than required fuel pressure, or a restricted exhaust. Another check would be compression, and leakdown. Can you get this misfire during a torque brake?[/quote:c669ff0190]


no not really. The computer shows some misfire when doing that but not that extreme to set code or make the vehicle shutter.
Apr 16, 2010 at 9:25 AM