Misfire at speed

FORD F-150
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JSH35601
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  • 4 POSTS
2000 F150 4WD, Automatic, 5.4 V8. 120K miles. Spararically, when the engine is warm, the truck starts to miss and backfire through the intake. It usually happens when the engine is fully warm. The problem continues until the engine is off and cooled down. Codes indicate no ignition misfire. The fuel pump has been checked and is within spec. Spark plugs and fuel filter have been changed with no improvement. This is crazy. Any ideas? Thanks jsh35601
Jun 2, 2007 at 8:48 PM
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HEAVYDUTY
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  • 60 POSTS
check coil on plug at pass.side rear. they have a coolant drip that can short them out
Jun 2, 2007 at 9:58 PM
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JSH35601
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Sir: My mechanic thinks that the intake manifold gasket is leaking coolant to the INSIDE of number 8 cylinder causing the problem. Is this possible? Have you heard of this problem before?

Regards

jsh35601
Jun 4, 2007 at 12:29 PM
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BLACKOP555
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yes it is possbile.0
Jun 4, 2007 at 1:50 PM
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