I was under the hood of R's 245 today, spun the crankshaft and heard air. I then noticed gunk under #2 spark plug, investigated further, and found the spark plug so loose it rattled around when I grabbed the plug wire! I feared the worst, but the threads seemed OK. After a trip to the hardware store for a 13/16" plug socket, I checked the other 3. All but #4 were loose with #3 also "wobbly" loose! I carefully hand loosened and tightened each and then torqued them down with no issues.

These (genuine Volvo) plugs were installed about a year ago by a local indy Volvo shop. It was my first tune up on the car (which has 320k mi), and I wanted the car in the shop should any trouble arise getting the old plugs out. I'm guessing those guys snugged them down but never went back with a torque wrench. Is there any other possibility you all can think of?

Extra credit: How on earth has the car been running so well with at least two plugs not sealing at all?? There's been neither a dip in mileage nor any drivability issues. I can't think of any damage that could have been done, but I'm really happy I caught it in the driveway before R was stranded somewhere when a plug fell out.

Weird stuff, and I guess a reminder to always check others' work--even the pros.

Best,
joe b.
portland, or
93 245 320k