where are the spark plugs on a 2003 ford f-150 5.4 litre
The plugs have coils on top of them and are located next to the cam covers on top of the engine. To get to them you need a 7mm low profile swivel head 1/4" drive socket with a long extension to remove the bolts holding the coil in place. Once the coil is removed you can access the plugs. I have done a lot of these and once you have done a couple they are pretty easy and you can save a lot of money over having the shop do it. It is worth spending $10 bucks or so for the special socket.
The rearmost plugs can be a bit difficult but if you have the right tools - extensions and swivels it is not that bad. I use a step stool and bright light to help with access and visibility.
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