First, let me preface this by saying that this is not at all typical. I've just been having a lot of hassles with cars lately. I've had 15 Chrysler minivans over the past dozen years, and most of them have been delightful to own and maintain.
We have a 1999 Voyager with the 2.4L engine that we've been driving for the past two years as our family vehicle, and it's been great. It's always had an oil leak that I finally decided to get rid of. It was coming from the valve cover, more specifically the #2 spark plug well which has always been full of oil. I could never get this spark plug out because I couldn't get the socket to go down on the plug. I figured there must be a bunch of cooked, gummy oil around it. Well, I finally decided to change the plug and the valve cover gasket, and solve both problems this week.
When I got the valve cover off I discovered that I didn't just have a leak on that spark plug well, there wasn't a gasket there at all! Also, the spark plug wasn't surrounded by cooked goo, it was stuck in place with some kind of adhesive because the threads were trashed. The new plug didn't have any grab at all in the hole.
I thought hard about this problem for a few hours. I figured I could drill and tap the hole and insert a new thread, which would require removing the head to avoid getting chips in the cylinder. Or I could change heads, or there might be some other solution.... I finally decided to clean it up really well and JB Weld the new plug in place. I let it set overnight. I was afraid to start the engine today, but I finally went ahead and did it, and it works great! This has always been a good running and reliable engine. I just wonder what was wrong with the former owner, stripping spark plugs out, gluing new ones in, omitting gaskets, etc. It already has 200,000 miles on it, so I figure I probably won't have to take that plug out again as long as I own it....