Changed My Spark Plugs - Question on frequency
11-22-2017, 02:55 PM
#1
Senior Member
Thread Starter
Changed My Spark Plugs - Question on frequency
So I went ahead and changed out my spark plugs. The manual states it isn't needed until 100K but have read many threads where people are doing them every 20K-30K. That seems a little ridiculous to me so what interval do you do?
At any rate, 2013 FX4 3.5 Eco with 62K on it. All 6 pulled still looked pretty good with only burn marks less than a quarter way down and were gaped at .040 consistently.
Ordered new SP534's from amazon and although it stated they were gaped at .035 mine came in at .030, at least according to my gauges. I left them as such since I was getting conflicting info of .028-.035.
I am not sure why people change them so often since all 6 of mine looked good and were gaped consistently although using older specs. Truck ran fine just wanted to do it. Hard to tell any difference but I swear it seems much quieter like, I couldn't even tell the truck was on quiet and it rides smooth. Fairly easy job with the only difficulty getting the back two on both sides and removing the clips on all 6. Took me about an hour but should be about 30 minutes next time.
This link has specs.
http://www.fordservicecontent.com/Fo...G1660912&div=f
At any rate, 2013 FX4 3.5 Eco with 62K on it. All 6 pulled still looked pretty good with only burn marks less than a quarter way down and were gaped at .040 consistently.
Ordered new SP534's from amazon and although it stated they were gaped at .035 mine came in at .030, at least according to my gauges. I left them as such since I was getting conflicting info of .028-.035.
I am not sure why people change them so often since all 6 of mine looked good and were gaped consistently although using older specs. Truck ran fine just wanted to do it. Hard to tell any difference but I swear it seems much quieter like, I couldn't even tell the truck was on quiet and it rides smooth. Fairly easy job with the only difficulty getting the back two on both sides and removing the clips on all 6. Took me about an hour but should be about 30 minutes next time.
This link has specs.
http://www.fordservicecontent.com/Fo...G1660912&div=f
11-22-2017, 03:40 PM
#2
Senior Member
Did you buy the truck new? I changed mine at 72,000 miles and they were gaped at .056 and above at that mileage. It didn't appear the original owner ever had them changed. .030 is the correct gap. It should be somewhere around .028-.032 and .030 is right in the middle.
Most people change them out sooner because the eco has rough idles if the gap is wrong. Like you said, it runs better with the new plugs, this is for a reason. The turbo's cause extra pressure so the spark gap is more important as the space in the cylinder is less forgiving if it is a little late or early.
Most people change them out sooner because the eco has rough idles if the gap is wrong. Like you said, it runs better with the new plugs, this is for a reason. The turbo's cause extra pressure so the spark gap is more important as the space in the cylinder is less forgiving if it is a little late or early.
11-22-2017, 11:20 PM
#4
Senior Member
It's more critical on a tuned EcoBoost, and the increased boost can actually blow out the spark if the plug is gapped too big. .030" is as good as you can get on a stock motor. I change mine at about 20K or so, whenever I feel the idle isn't "perfect". 