Loose spark plugs with secured ignition coils

[y_p_w]

I supposed most have heard of loose spark plugs flying out of the tube when not properly tightened, but that was typically with plug wires and connectors that are held down via relatively loose friction.

So what's the worst that could happen with a plug that's held down with a direction ignition coil? I was thinking that they don't exactly press down on the plug. Still - since most are held down with a nut, I didn't think the plug would come out flying into the hood.

 

[yonyon]

It still comes out of the hole, but when it does it smashes the coil and then just rattles around there. The annoying part about the threads in the head getting borked is still the same.

Edit:
The Ford 2-valve 5.4L was famous for spitting plugs out. The bolt typically couldn't hold the smashed coils in but the fuel rail did.

 

[The_Jeff]

The plastic whatever that holds the coil down won't resist the 150 PSI trying to shoot it out.

Also since it just ate the last of its threads before coming loose it's already got a running start.

 

[bdcardinal]

Originally Posted By: y_p_w
I supposed most have heard of loose spark plugs flying out of the tube when not properly tightened, but that was typically with plug wires and connectors that are held down via relatively loose friction.

So what's the worst that could happen with a plug that's held down with a direction ignition coil? I was thinking that they don't exactly press down on the plug. Still - since most are held down with a nut, I didn't think the plug would come out flying into the hood.


My mom's 00 Grand Marquis launched a plug and it blew the coil off the intake. I found the coil sitting with the plug still in it and the plastic tab that bolts to the intake was still on the intake.