2007 Ford Expedition EL Check Engine Light Blinking

[Wildbill1]

I installed the Accel coils on my '07 6 months ago when I changed plugs and just had one go bad. I just ordered a set of OEM Motorcrafts after reading on other forums that the aftermarket coils are junk.

 

[Habbibie]

Just out of curiosity, why do you guys change all coils all at once? They're expensive and only need replacing the individual failed coil the other 7 can stay, if a coil fails it fails all the way and if it works it works all the way this item doesn't deliver half power if it's "wearing out"