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OIL on SPARK PLUGS (passengerside)4.6


Old 01-23-2002, 12:59 AM
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Unhappy OIL on SPARK PLUGS (passengerside)4.6

My husband and I just changed the plugs in our 97 F-150, 4.6L, 124,000 miles. The drivers side were perfect, but when we got to the passenger side the plugs had oil on them. The closer to the fire wall we got, the worse the oil got on the plugs. When we pulled the socket out of the one by the fire wall, almost the whole socket was covered in oil. Can anyone lead us in a direction. We are hoping for valve cover gasket?? I've read up here on f150 online and found a lot of heads leaking oil!!
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Old 01-23-2002, 02:28 AM
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Location: central california
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if the oil was on the outside of the plug, not the cyl. side. it's most likely from vavle cover. the head gasket is much lower on the head than where the plug hole is. it's common for oil to settle there. it's also common for water. and that is not good for the plug or the wire. so when you wash your engine. you should alway's drive it for awhile. so the engine temp will evaporate the water that did get in there. and when changeing plug's, put that lube for ign. sys. in the plug boot. it help's alot the next time you change the plug's. stop's the tearing of the boot's when removed next time. and keep's normal moisture out. good luck.
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Old 01-26-2002, 02:03 AM
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Location: Woodslee, Ont. Canada
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If you have oil leaking into the spark plug holes from the cam cover gasket you should also be seeing oil on your driveway. The oil has to leak past the gasket to the outside of the engine and down into those holes. It will migrate to a lot of other places before it fills them up. The cam cover gaskets on the modular engines are generally very good for keeping things sealed up.

Take a good look down in the holes for any sign of porosity in the cylinder head - seen a few where oil migrated through porosity in the head and into the spark plug holes causing this concern.
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Old 01-26-2002, 04:44 PM
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There's not any oil on our driveway. Do you think this could be the intake leaking the oil into the spark plug chambers???? We picked up a valve cover gasket today - we will tackle that this weekend - we're going to get down in those holes and dry them out really good and see if this helps. A guy at Ford didn't really have a clue!! OF COURSE NOT - right? Today the CHECK ENGINE light came on and it's running really sluggish. I think the oil is fouling out the plugs. If anyone has any more suggestions - we'd appreciate it!! Thanks for all of the replies!
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Old 01-26-2002, 09:56 PM
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Location: Woodslee, Ont. Canada
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You may not have installed one of the spark plug boots fully which could be causing a misfire concern.

The oil won't foul the plugs unless the engine is burning it real bad (worn rings, valve seals, etc.) - does your engine burn any oil?

The only leaks you could possibly get from the intake are coolant or vacuum. There are no oil passages in the intake.

Again, check for porosity along the I.D. of the spark plug holes (below where the spark plug boot would seal against). I'd be willing to bet oil is migrating from the high-pressure feed gallery through the porosity and into those holes. If the truck has gone 100K+ miles and they only have a minor amount of oil in there, I would just clean them out, install new plugs and forget about it.
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Old 01-26-2002, 11:52 PM
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Location: Montana
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What kind of plugs did you put into it, it seems that in the modular engines stock plugs work the best. I have seen the split fires and the bosch +4 both cause the misfire code.
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