Spark plug loosens and then tightens again on removal

BILLYD2916

MEMBER
2006 MAZDA TRIBUTE
2.3L
4 CYL
2WD
AUTOMATIC
220,000 MILES

I have changed 1 plug but when I moved to the second it was almost removed and then tightened up again. The same with 3 and 4. Shaould I just power it out or should I be worried about something breaking or stripping?

Thursday, July 24th, 2014 AT 4:34 PM

1 Reply

FREEMBA

MECHANIC
1,152 POSTS

DO NOT POWER IT OUT!
The plug is seizing to the cylinder head (usually from the heat of combustion).
Saturate the plug area where it enters the cylinder head with a good quality spray penetrate. BUT, DO NOT POWER IT OUT! If it remains difficult to remove, allow a shop to do it, but warn them (ahead of time) that the plugs are stuck in the cylinder head.

This is one recommended method you may be able to do yourself.

Apply a good penetrate like Deep Creep and run the engine up to full temperature before trying to unscrew the plug. The aluminum cylinder head will expand more than the steel body of the spark plug. If you're lucky, the plug may come out without significant damage to the threads in the cylinder head.