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So with about 75,000 miles on the factory plugs and winter setting in hard on the north Country I figured it's a very good time to go ahead and change the factory plugs out. I was just planing on purchasing OEM motorcraft plugs and hit a snag. Did ford have two different spark plugs for the 5.0 F150 possibly a standard duty and heavy duty? Or could it have been a updated plug type?
My truck had a extremely clogged air filter when I purchased it. The female owner had never changed it in 69,000 miles. She also lived in a area where they used sand on the roads so you can guess how bad the filter was. I picked up 2MPG and noticed a good bit of power gain when I replaced it. However I have noticed the truck has been running kind of rich recently and I am wondering if the clogged filter may have caused the plugs end life early. Of course 75,000 miles is pretty good for spark plugs in my book.
My truck had a extremely clogged air filter when I purchased it. The female owner had never changed it in 69,000 miles. She also lived in a area where they used sand on the roads so you can guess how bad the filter was. I picked up 2MPG and noticed a good bit of power gain when I replaced it. However I have noticed the truck has been running kind of rich recently and I am wondering if the clogged filter may have caused the plugs end life early. Of course 75,000 miles is pretty good for spark plugs in my book.
Yikes... I'd advise pulling a plug and looking at it. How did you determine that it is running rich?
I would also ensure that the new plugs are gapped correctly. I hear that is a problem, even with fresh plugs straight from the box. That's something I'll be looking at when I change my plugs soon.
Also, to the guy with the clogged air filter, you may want to reset your KAM and see if that helps with the rich mixture. The computer may have learned to adjust the fuel ratio to compensate for the clogged filter. It would probably be best to clear the KAM and have the computer re-learn its strategies with the fresh filter.
I put the SP-548's in mine back in June around 75,000 miles and gapped them to .045. At the time the SP-519's were in short supply and no one had them and Ford Parts is even showing the 548's for the 5.0L. The only differences between all three of them is how they come gapped from Ford, some are pre-gapped for Ecoboosts motors. Otherwise, they are all the same plug.
I did check the gap and the old plugs came to roughly 0.060.
WAY too much. I'd regap, reset the computer, and see how it runs after that. If it's still rough then change the plugs as you're starting to get close (ish) anyway.
12-09-2016, 10:21 AM
5.0 updated spark plugs?
