Zetec 2.0 Spark Plug Popping Out
So today I was driving and one of my spark plugs came out of the head. Car was running fine before hand. I didn't have a wrench on me so I had it towed home. Put the plug back in and drove it a few miles. Ran fine till the plug came out again.
The first time The gap was totally closed. I opened it back up before I re installed. When it popped out the second time the gap was closed again. It doesn't look hammered though. I haven't tried to put it back in yet. The threads were still in the head after it came out the first time. I hope they're still there now.
I haven't taken one of these engines apart. What could cause something like this?? Did I just not tighten the plug?? Even then, the gap being closed, something must be hitting it.