Oil On Spark Plugs

What year, miles and model? Which plugs had oil on them?

Oil on the top of the plugs, down in the plug holes and on the plug wire/COP boots and not on the electrodes and threads, right?

If it's on the outside then a valve cover gasket is likely or something leaking in the PCV system. There's no oil passages in the intake manifold.

you sure its not a cracked intake and that residue is not dirty coolant?

Clean off that area on the head between the valve covers and intake where the spark plug holes with some degreaser and track it for a while and see if you can see where it's coming from. Sometimes it's hard to tell if it's water because it'll evaporate off while the heads are still hot but oil should leave a trail.


Have the valve cover gaskets been off before? It's easy to get them twisted or pinched when you put them back on - they love to snag on the cam cap bolts and timing gears and everything else under the hood when you're trying to wrestle the covers back in to place. They're pretty durable and forgiving though - you may try retorquing the valve cover bolts first if you determine that's where the leak is from.

You'll want an assortment of regular and deepwell 1/4" sockets, extensions and U-joints - some of those bolts are a tight squeeze to get at, especially on the passenger side. On mine they're mostly 8mm heads with a couple of 10mm - not sure about yours.

The bolt by the strut tower on the passenger side is next to impossible to torque down properly - I had to experiment with finding the right amount of force with that combination of knuckles and extensions at that angle on another, more accessible bolt first 'cause you're hitting that bolt at almost 90 degrees.

If you end up pulling the covers off, a thin bead of RTV in the grooves in the cover will help hold the gaskets (old or new) in place when you put them back on. Old gaskets can stretch a little bit and will want to poke out somewhere and when you poke it back in, it will poke out somewhere else. Argh. And, like I said before, the gaskets love to catch on all those cam cap bolts and towers and gears and whatever else they can hook on to. Between that and gravity, the RTV makes it a lot easier to get the covers back on with the gasket in place.

A dental mirror will help you verify that the gasket is still in place once you finally get the covers back over the cam towers and gears. If it has gotten pulled loose somewhere, you can probably run your fingers along it and work it back into place without having to pull the covers all the way back off again.

There shouldn't be anything that can't handle a little degreaser for a few minutes under there, but yeah, try to keep it and water (especially if you pressure wash) out of the obvious stuff like electrical connectors and components. Don't let it sit on the plugs and boots too long either - make sure those are dry (compressed air is your friend) before you fire it up but the running the engine will help dry everything else off.

You wouldn't believe how many threads there are on the internet that start out "I cleaned my engine and now it won't start/misfires. What could it be?"

Getting the covers out isn't as bad because you can just manhandle them but getting them back on is trickier because you don't want to tear up the gaskets. The clutch cable gets in the way on the driver side and the A/C lines interfere on the passenger side. The first time I had mine off, the driver side gave me more trouble but the last time, the passenger side did.