Mercury overheated i think?

have a 1989 Mercury grand marquis. the other day cruising down the highway going 65 it started misfireing like crazy then lost power, finally stalled, coasted off road and saw nothing but steam from under hood. no warning lights came on. car would crank real slow but not start. went back next day and car cranked normally and started but ran extremely rough, got it off the side of the highway to a wal mart parking lot where it died again. cranks but won't start. let sit there 2 days, went up today, it started, runs rough again. made it a few feet and it stalled, back to just cranking. pulled plugs and all are oil fouled. and the rear 2 are melted. the worst one was drivers rear. WTF?

any ideas what happened. and it pours smoke out exhaust when i crank it..

pic attached of 6 of the 8 plugs.

BTW plugs are only like 3 months old

http://i5.photobucket.com/albums/y185/TempoBoy1992/2013-11-22161802_zps5d0c2117.jpg

http://i5.photobucket.com/albums/y185/TempoBoy1992/2013-11-22161829_zps92feb93e.jpg

Pull the dipstick. What's it look like?
5.0 liter?

5.0 / automatic. oil is clean. just changed a few weeks back, not milky at all..

There are a couple things this could be sometimes your electrical system will push to much pressure causing the oil sending unit to act up(or that just being problem in general) and also putting to much current thru your plugs causing those to melt check distributer/ coil pack with volt meter they could be pushing to high.

Start with why it overheated. Pull all plugs,crank the "cold" engine over and see what spits out of each cylinder. How's the cooling system?

Sounds like a lower intake gasket replace that whatever antifreeze got through...after replacing gasket let your ride run for a while she will smoke out of exhaust

have a 1989 Mercury grand marquis. the other day cruising down the highway going 65 it started misfireing like crazy then lost power, finally stalled, coasted off road and saw nothing but steam from under hood. no warning lights came on. car would crank real slow but not start. went back next day and car cranked normally and started but ran extremely rough, got it off the side of the highway to a wal mart parking lot where it died again. cranks but won't start. let sit there 2 days, went up today, it started, runs rough again. made it a few feet and it stalled, back to just cranking. pulled plugs and all are oil fouled. and the rear 2 are melted. the worst one was drivers rear. WTF?

sounds like a valve problem with perhaps bad valve stem seals. blue smoke out tailpipe?
any ideas what happened. and it pours smoke out exhaust when i crank it..

pic attached of 6 of the 8 plugs.

BTW plugs are only like 3 months old

http://i5.photobucket.com/albums/y185/TempoBoy1992/2013-11-22161802_zps5d0c2117.jpg

http://i5.photobucket.com/albums/y185/TempoBoy1992/2013-11-22161829_zps92feb93e.jpg
sounds like a valve problem with perhaps bad valve stem seals. blue smoke out tailpipe?

Hey yea that seems right either bad valve stems or your rings could be hit....do a compression test on each cylinder

I would make a bet that this is due to valve stems

I would very much like to hear more from you on this subject.

well, once i get the thing home (hoping for tomorrow) it's sitting till spring other then replacing a shattered door glass.. lol

2000 Mercury Sable Overheating? please help if any possible solution,thnx