GEN 1 Replacing Spark Plugs on Roush 2013

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Red69

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Howdy all…. my truck has not been running well, and this plug thread was perfect! I’m moving forward with the the plug and wires change. So far, removing the splash shields was a great recommendation for getting all the lowers out. Electrical tape on the socket swivel was also a great tip to keep it on the proper angel to reach those lower plugs. My 2014 beast has 65k on it and so far I have at least 5 lower plugs that were broke. What’s up with MOTORCRAFT PLUGS? Moving to the top … reading the threads on pulling the Roush “spacer”… sounds challenging… but not impossible. Any other tips appreciated! I have a BMW S85 so I’m use to the tight spaces … spacer bolts seem to be the challenge to get to those last two coils…. Thanks!
 

StevenStarke

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Any benefit to changing plugs on a stock 2014 truck with 50k miles? I feel like there is an ever so slight miss at idle. and Ive never even been in another raptor to compare it
 

BalanBro

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Any benefit to changing plugs on a stock 2014 truck with 50k miles? I feel like there is an ever so slight miss at idle. and Ive never even been in another raptor to compare it
Possibly. Mine felt like it had an occasional miss at idle, but seemed fine otherwise. This was when I bought it last year with 68k.
Recently at 80k, I noticed a ticking sound coming from the driver side, so I decided to investigate. Came to find at least one of my coils occasionally arcing on the fuel rail and cylinder head. A bit more research and I come to find this is a very common issue on the 6.2 used on raptors and F250s. So I decided to replace all my plugs and coils with new Motorcrafts.

I just completed the job, removing each plug from a warm (not hot) engine. Getting to some of the lower plugs was a pain. The two most difficult were the passenger side by the shock tower, and the rear most driver side, up against the firewall. So here are my observations and assumptions:
All the plugs looked okay given the mileage. Actually, someone changed the top 8 plugs before, as they were a cheaper set with a platinum electrode. The bottom 8 were definitely the original, but didn't look bad at all. Could have easily been regapped and run for more miles, but for the cost, who cares?

I think the real issue is the coils. There is an internal resistor "pill" in the upper coil unit. All of them were corroded. What I believe happens, is the corrosion causes a poor connection between the coilpack and the plug, so the electricity goes though the path of least resistance, which happens to be through the vent holes in the coilpacks and to the nearest grounded metal object. When this happens, I believe the upper spark plug will not fire. However, since the 6.2 has a wasted spark system with two plugs, the lower one continues to fire so you don't get a complete misfire that would trigger a check engine light. After putting in new coils, the ticking noise is completely gone, idle is very smooth, and throttle response off idle and at low rpm is MUCH improved.

I heard there are boot kits to rebuild the coil packs with a new resistor, but I can't for the life of me get the old resistor pill out since it's corroded way up in there.


TL;DR
Your plugs may be fine, but the coils are suspect.
 

FishFreak

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Possibly. Mine felt like it had an occasional miss at idle, but seemed fine otherwise. This was when I bought it last year with 68k.
Recently at 80k, I noticed a ticking sound coming from the driver side, so I decided to investigate. Came to find at least one of my coils occasionally arcing on the fuel rail and cylinder head. A bit more research and I come to find this is a very common issue on the 6.2 used on raptors and F250s. So I decided to replace all my plugs and coils with new Motorcrafts.

I just completed the job, removing each plug from a warm (not hot) engine. Getting to some of the lower plugs was a pain. The two most difficult were the passenger side by the shock tower, and the rear most driver side, up against the firewall. So here are my observations and assumptions:
All the plugs looked okay given the mileage. Actually, someone changed the top 8 plugs before, as they were a cheaper set with a platinum electrode. The bottom 8 were definitely the original, but didn't look bad at all. Could have easily been regapped and run for more miles, but for the cost, who cares?

I think the real issue is the coils. There is an internal resistor "pill" in the upper coil unit. All of them were corroded. What I believe happens, is the corrosion causes a poor connection between the coilpack and the plug, so the electricity goes though the path of least resistance, which happens to be through the vent holes in the coilpacks and to the nearest grounded metal object. When this happens, I believe the upper spark plug will not fire. However, since the 6.2 has a wasted spark system with two plugs, the lower one continues to fire so you don't get a complete misfire that would trigger a check engine light. After putting in new coils, the ticking noise is completely gone, idle is very smooth, and throttle response off idle and at low rpm is MUCH improved.

I heard there are boot kits to rebuild the coil packs with a new resistor, but I can't for the life of me get the old resistor pill out since it's corroded way up in there.


TL;DR
Your plugs may be fine, but the coils are suspect.
Wow well that would be cool to be able to rebuild the coil packs with a new resistor. I got my 2014 Screw with 130k miles and the plugs have never been changed. I got 16 plugs and the wire kit, so that's next, but if you figure out where to get that resistor, please advise, my Northern CA truck has no rust so I may be able to pull that repair off.

I too have the slightest miss at idle, however, no ticking noises and throttle response is nearly instantaneous (compared to before) with my 5 star tune. Plugs will hopefully smooth the idle out and make it even more fun to drive!
 

BalanBro

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It's basically these things.


It includes a replacement boot, resistor and spring conductor. The resistor pill in my case was stuck in the oil coil pack (albeit, I didn't work too hard trying to get it out since I bought new coils anyway). Maybe if you have a skinny magnet pick-up tool, you can stick that into a coil and see if that's enough to pull it out. You may have better luck than me though, being in CA.
 

FishFreak

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It's basically these things.


It includes a replacement boot, resistor and spring conductor. The resistor pill in my case was stuck in the oil coil pack (albeit, I didn't work too hard trying to get it out since I bought new coils anyway). Maybe if you have a skinny magnet pick-up tool, you can stick that into a coil and see if that's enough to pull it out. You may have better luck than me though, being in CA.
Awesome Balan! Thanks!

Stupid question: how many of these do I need? 8 or 16? Those resistors have got to be on all 16 plugs right?
 
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FishFreak

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Thanks @BalanBro and I found those resistor pills, springs and boots for our 6.2's for several bucks cheaper on Rock Auto. Is the spring and the resistor only on the plugs the coil sits on or is there a resistor under something for the secondary spark plugs? Do I need 8 or 16 spring, resistor & boot kits?
 

Tommysyko

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Thanks @BalanBro and I found those resistor pills, springs and boots for our 6.2's for several bucks cheaper on Rock Auto. Is the spring and the resistor only on the plugs the coil sits on or is there a resistor under something for the secondary spark plugs? Do I need 8 or 16 spring, resistor & boot kits?
Did you get this done? I heard it was going to be sketchy to effectively rebuild these and just went with new wires. I'm going to tackle the change out with a Whipple this holiday. Hope everything runs smoother after.
 

FishFreak

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Did you get this done? I heard it was going to be sketchy to effectively rebuild these and just went with new wires. I'm going to tackle the change out with a Whipple this holiday. Hope everything runs smoother after.
I did not get to this project, it's number 9 on a long list of 'priorities', if ya know what I mean? I'm glad @BalanBro replied that we only need 8 coil boots and resistors for our 16 plug engines. Rock Auto has several, and note, some come with the resistor and some don't. Some are 'rubber' boots and some are listed as silicone, some don't say crap. I'm going with silicone Standard Motor Products, NOT the economy version, cuz of this. I think silicone may last longer than plain rubber? I may try to do the plugs this long weekend as well, but after I replace my Raptor's sunroof track system :-O !! I've also got a new serpentine belt and all idler rollers to install cuz at 133k miles, that belt has got to go!!

Good luck with yours, but I think that Whipple won't deter much, the plugs and coils are at head-center or below. Yea my n/a 6.2L just has the slightest miss at idle like Steven Starke said up there, but runs like a ***** ape on throttle. Hoping mine will smooth out too....
 
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