Coil and plug
3 Answers
Buy a new set of plugs and coils on Amazon. You will save a lot of money. I just bought a set for my F150 for under $100.
BTW your engine uses the infamous two piece spark plug. Buy the newer one piece plugs and if you do the work yourself buy a broken plug removal kit and soak the old spark plugs with penetrating oil overnight.
All 8 coils are not likely bad. If you replace the coils I recommend you buy Motorcraft made by Ford versus the aftermarket equivalent. The Motorcraft parts cause very few issues when compared to the aftermarket stuff which is hit or miss. Which engine do you have?