spark plug change

[02tman]

I just bought an 02 with 90k mi. I want to get best mileage and performance and figure I should change the plugs. There's lots of scary stories about spark plugs breaking. The dealer says $675!
How often do plugs break? 5% of the time or 50%?
Does the plug problem happen with 02's? One thread says the plugs spit out on the 2-valve and stick on the 3-valve motors. I think my 02 is a 2-valve for an 02.
Any advice?

 

[2k3Expy]

Yes you have the 2 valve and I had 122k on my 03 plugs before changing. Just take it easy and you'll be fine.

 

[1997SCEBFEX]

For my first round I took the plugs to the Blue Oval folks, did the second round myself though.

 

[paul_smith_347]

The biggest thing to watch out for when doing your own plugs is tightening the new ones down. The best way is with a torque wrench. I think ten pounds is all it takes. Anyways, the reason behind all this is the heads. I don't know if Ford just cast cheap alum heads or didn't heat treat or what the issue is exactly, but if you over tighten the plugs it causes the alum threads to streatch in the head. About 20 to 30 thousand miles after that you will be driving along and hear a Loud bang. That is the sound of your spark plug blowing out of the head. After the threads have been streached from over tightening, they simply don't hold the plug down goood enough. As you drive the plug works its way loose untill the last thread or so can't hold the pressure and boom. My expy now has 4 heal a coils in it from this now. All it comes down to is that someone in the past over tightened the spark plugs.

 

[Jason_CPAPS]

kind of off topic here but did the head have to be removed for the heli coils

 

[paul_smith_347]

No, but it takes a special tool and a right angle drill to do 4 and 8. Shop I went to has done several in the past so they had the tool and drill. I was just charged straight labor.