Oil fouled plugs 7 & 8
 

I've been searching the archives for this problem, and although some have had similar problems, none are quite the same....
When I changed the plugs last summer, the 7,8 plugs were carbon and oil soaked....the rest seemed fine, light brown insulator and clean....
I'm gonna pull 7, 8 today and see what I have now, but as a prerequisate, has anybody seen this...I can understand 1 bad plug, but both rear plugs? Hmmmmm.....:rolleyes: I also wonder if the dual quads might be helping the problem, but that is only conjecture on my part...
Additionally, if I install r46ts plugs in the 2 back cylinders, "might" that help resolve the issue??

If you are sure it's oil and not gas you likely have a ring problem with those 2 cylinders. Only way to know for sure is to do a leakdown and compression test. A hotter plug may minimize the fouling but not correct the underlying problem. How does it run? Is it misfiring or burning oil?

does it smoke when first stated up?
then clear after running a bit?
if so it could be guides and seals on your valves.
otherwise rings would be the best guess.

Do you have an auto trans.if so the modulator could be bad.

Another possibility is your intake gaskets...mine went toast after 95,000 miles and No 8 plug would oil foul every 600 miles or so in the 78..had fun finding that one..

Concur with rihwoods. Go see if your intake bolts are loose. It's cheap.

Thanks for all your help and suggestions....as I've found in many parts of this car as I went thru it, the previous owner(s?) was a slug when it came to basic car maintainence (just gas it and drive it)...for all I know, the plugs I pulled the first time MIGHT have been installed at the factory, 100k ago :rofl:
Pulling the 2 suspect plugs yesterday, I found a very, very little carbon, and generally speaking they were fine, so I guess this was a false alarm post...sorry...but thanks again for chiming in :thumbs:

Well, helpful for me as I have the same problem and had been following the thread. Now I know what to do...if the car ever gets here. It's been on a truck coming from Vegas....Jeez, he must be driving on the back roads! Every day is torture!