guardrail22

turned 69000 miles last night on my 2012 F150 CCLB EcoBoost

Have my plugs, waiting on boots. Changing them based on what I see here.

Local shop gets $160. Ford wants $220.

What's everyone's favors spark plug gap for the SP534s?

I've seen .028, .030, .034.

05 super

Why not do them yourself?
Pretty easy job
I gapped mine to .028..runs great.

meaz93

.028
Super easy to pull....took like 20min in and out!

guardrail22

Seems tight for high energy ignition. How's fuel mileage?

Sirikenewtron

The boost likes a tighter gap, MPG's do go down though with the tighter gap but truck pulls hard.

Sirikenewtron

If you're not tuned .030 is fine

guardrail22

New plugs in. Mileage seems down. Especially in town. Will get a better check going home Friday night.

Sirikenewtron

Did you gap them to .030? If you're not tuned you'll most likely see better mpg's gapped at that if you didn't gap them to that. The lower gaps are better for tuned but mpg's will suffer a little

guardrail22

gapped at 30 and new boots

guardrail22

finally found my feeler gauges and got to check the old plugs. All six plugs are at .038" No signs of tip wear but interestingly three of the plugs are black all the way up the threads, three are clean beyond the 3rd or 4th thread. Could be the black ones are from the side where the crankcase ventilation is drawn to.

Have a picture - just need to figure out how to get it here.