P0300 and oil on the #7 spark plug
 

I have a 2001 5.3 Sierra that has a flashing SES light with the P0300 code. After checking the spark plugs I came across #7 and it was dripping with oil. click for picGuessing bad head gasket? Any suggestions or tips before I start tearing this engine down? If it is the head gasket, how hard is it to get the old one out?

Headgasket would mean coolant to me, like tons of white smoke out the tailpipe and sweet smell to it.

If it's covered in oil, I'd tend to think it's getting past the piston rings and into the cylinder or through the intake down the valve and into the cylinder.

Alright, well that pretty much sucks. Makes perfect sense now that I think about it. Guess it's time to start getting some quotes.

You could do a compression check on that cylinder to see what it's reading aswell.

Dripping in oil means one of two things:

Busted piston
Intake manifold awash in oil.

If you've got good compression, the oil likely came down the intake. If you don't have any, well...

you need a new drivers side valve cover. take it into the dealer. there is a bulletin/special policy.