08WHITE4X4CREW

I bought a 2012 f150 ecoboost 2 months ago and sometimes when driving about 55-60 mph I get a miss when accelerating up hills. I am going to change my plugs since the truck has 70000 miles and I don't know if they have ever been replaced. I got the motorcraft sp534 plugs. Should I leave them gapped at the .35 they are at out of the box? The truck is completely stock and I have no plans to add a tuner right now. I have read about .30 on here but that seems to be for tuned trucks. Anything special I need to know about changing them.

Live4Him

Interesting. I just did the plugs on my 2012 and used the Motorcraft SP534s and mine were right at .030 out of the box. Stuck 'em right in and the truck runs like new again.

08WHITE4X4CREW

Ok I actually haven't checked them but I got them from rock auto and their site said they were .35. I will have to check them.

Chad Walker

Same here. Mine were gapped at .030 as well. Some with tunes are running .028. .030 should be the sweet spot.

Tothemax

Gap them at .030 and use a torque wrench when you install.

Also, if you already havent, drill a weep hole in your intercooler. That way no water will build up.

Ectoboost

You will want to read up on the acceleration issues... Plugs will fix for a little while, but the reason for the "miss" is the condensate from your intercooler getting passed through (blows out spark). The best way to fix that is a drain hole in the intercooler.

pet575

Along with the plugs at .030 and drilling the hole in the intercooler, look into replacing the lower coil boots. I am battling the exact same problem as you. Changed plugs at 60K or so after buying it with 50K on it, worked for a few thousand miles and then it returned. Recently drilled the hole and changed plugs again (I'm now at 70K) and it has not fixed it. Ordered the lower boots and just received them a few days ago. Planning on changing them this weekend.

Poke around on here a bit, you'll find a number of threads on this problem. Trying to read the sticky one that is 150+ pages (or more by now?) takes too damned long, though.

08WHITE4X4CREW

I did get the lower boots cause they were only like $2 each. I figured why not replace them.

ffffpsh

I just ordered SP534 plugs today from amazon. I have the same slight shudder when going up hills under light to medium throttle.

I will let you know what I experience as I track down the problem. It is so minor it doesn't bother me but will do what I can to track it down.

People are drilling holes in the intercooler??? that seems like a bad idea

Ectoboost

The miss comes from the moisture in the intercooler getting sucked up and blowing out spark. Only way to get rid of that moisture is the hole.