Problem with engine misfire at mid throttle and under load

[SierraHawk]

I had posted a note about our 2003 5.4L engine misfiring at mid throttle and under load earlier. I wanted to do a follow up but somehow it has dissappeared.

FYI I had originally thought that this was a fuel side problem (ie, water in gas, clogged jets, etc)but could not find a remedy . Local shop in Bangor did a code check that basicly said we had to take it into Ford for the diagnostics. This was not a cheap fix ($470). They found that two of the sparkplugs and coils needed to be replaced. So far we have driven 4000 miles and have not had any similar problems emerge.

[Ateam]

You have a one of the coils on your spark plugs going out. I started replacing mine at 60000 and had one go out for the next three years. Tired of the cost of each one per year, finally replaced them all. Spark plugs good coils bad, dealer said there is too much heat build up in the van design compaired to pickups. Whatever.