Plug loose in head

[Scott S]

My lass has been out in the car and she called me to say it 'wasn't right'.

Just been to it and when I first started the car, there was a 'popping' sound coming from around the oil filler cap. Had a look through the gap and the lead was loose. When I took the upper part of the inlet manifold off and lifted the lead (closest to the cam belt side of the engine), the plug came out with it.

I instantly thought it had been pushed out by the piston and the threads were fucked (as well as probably a whole load of other parts), but looking at it, the threads were ok, the plug went back in, tightened up as you would expect (as in how you'd expect if it was a simple plug change) and the lead went back on (although in pretty poor condition from the bouncing around).

The car is now home (was only about 2mile away), but I am not certain how this could happen. The plugs have been in for 4k miles (about 6months) and the car has been running great until tonight.

Can a plug 'work its way loose'?
Are the threads in the head likely to be stripped (s**t question I know, as anyone replying won't have been able to see into the head).
Anyone heard of this happening to a Clio before, or am I unique?

 

[sideways danny]

not tighened up correctly/enough is most likely

 

[Scott S]

That was what I had thought, but seems odd to have done it after 4k miles and with no prior warning (she picked me up from the airport last night and nothing 'seemed' up).

Although, to be honest, I have never seen it happen before, so I am only applying what I think is logical.

 

[sideways danny]

seen it a fair amount, especially on F4R's

 

[MikeB]

Just sounds like its come loose will probally be ok.

 

[Scott S]

seen it a fair amount, especially on F4R's

I'm a bit more 'at ease' after reading that. Going to get some new plugs and leads tomorrow and also get the thread checked in the head.