People running the PR ignition set

335i_nick

Specialist
May 10, 2017
98
43
0
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335i
Hey guys. I am just trying to get some feedback from the guys running the Precision Raceworks ignition coil setup.

I have been running it since it came out, it's been absolutely awesome and only recently I have ran into a misfire problem. I am pointing at, to what I believe, is the gap of the plug and/or heat range of the plug.

I am running the 95706 2-step colder plug at a gap of .025"

I am getting a misfire INTERMITTENTLY above 5500rpms on full boost, which is 28-30psi (pure stage 2s)

Do you think the gap is too big? I am considering bringing it in to .022" and re-testing. Also, should I run the 1 step colder plug, like the 5992 (or newer number I forgot it)

What are you guys running?
 

V8bait

Sergeant
Nov 2, 2016
493
754
0
Texas
Seen this with too cold plugs with a big gap and high power the other day, called carbon tracking, I'm told it can also be a cracked ceramic etc too. Are you using dielectric grease? Might also help. You can see the spark going around the plug, since the couple cm air gap is less resistance than your .025" at full tilt. I don't think this was ever a thing with the underpowered factory coils, which I also used grease on.

received_10212048412919168.jpeg
 

335i_nick

Specialist
May 10, 2017
98
43
0
Ride
335i
Seen this with too cold plugs with a big gap and high power the other day, called carbon tracking, I'm told it can also be a cracked ceramic etc too. Are you using dielectric grease? Might also help. You can see the spark going around the plug, since the couple cm air gap is less resistance than your .025" at full tilt. I don't think this was ever a thing with the underpowered factory coils, which I also used grease on.

View attachment 4672

Yea. that's my picture I sent to Rob. haha

I replaced those plugs with new ones, greased up and now im still getting misfires.
 

335i_nick

Specialist
May 10, 2017
98
43
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335i
Rob is going to send me new wires. Going to try that. I just wanted to check here if anyone had gap advice. Like antiochasylum said to lower gap to .022. I am going to try that too.
 

Bmwfixerguy1

Lieutenant
Jun 5, 2017
873
288
0
Ride
07 335i MT
Seen this with too cold plugs with a big gap and high power the other day, called carbon tracking, I'm told it can also be a cracked ceramic etc too. Are you using dielectric grease? Might also help. You can see the spark going around the plug, since the couple cm air gap is less resistance than your .025" at full tilt. I don't think this was ever a thing with the underpowered factory coils, which I also used grease on.

View attachment 4672

Oh my goodness that's text book carbon tracking! You could put that pic in a Chilton manual lol
 

JAperformance

Specialist
Feb 13, 2017
90
44
0
Ride
09 335i
I'm running Pure S2 28-30psi with 95770 @.025 gap, so far no misfire issues.

On a side note I ran a my JB4 for about a week last month to do some test and was having cyl 6 misfires same setup. Fixed it with some bef adjustments on the fuel side.
 

titium

Private
Nov 8, 2016
48
9
0
Australia
Seen this with too cold plugs with a big gap and high power the other day, called carbon tracking, I'm told it can also be a cracked ceramic etc too. Are you using dielectric grease? Might also help. You can see the spark going around the plug, since the couple cm air gap is less resistance than your .025" at full tilt. I don't think this was ever a thing with the underpowered factory coils, which I also used grease on.

View attachment 4672

Impressive! Guessing this will show up more as more kits get sold especially with coils/plugs coated in oil from valve cover leaks.
 

Ztuck45

Private
May 16, 2017
32
37
0
Ride
2010 335i
IMG_2863.JPG
I am having a similar problem. I'm running .022 gap.

My setup is docrace 6266, e50, no pi, and precision coils. This is what my plugs look like
 

Bmwfixerguy1

Lieutenant
Jun 5, 2017
873
288
0
Ride
07 335i MT
So what's going on here is the type of plug wire for the type of plug being used.
Carbon tracking comes from an air gap thats easier to jump under load.
So since the factory plugs and factory coils don't have a gap because they use the friction fits to hold it all in place its not a common problem.
I can only assume that the wires being used have a snap fit? The boot will be tight but it's clearly not as tight as factory would be.
I think a healthy slather of dielectric grease when installed is a super simple fix here :)
 

335i_nick

Specialist
May 10, 2017
98
43
0
Ride
335i
So what's going on here is the type of plug wire for the type of plug being used.
Carbon tracking comes from an air gap thats easier to jump under load.
So since the factory plugs and factory coils don't have a gap because they use the friction fits to hold it all in place its not a common problem.
I can only assume that the wires being used have a snap fit? The boot will be tight but it's clearly not as tight as factory would be.
I think a healthy slather of dielectric grease when installed is a super simple fix here :)

Grease was used. Same result :(
 

Bmwfixerguy1

Lieutenant
Jun 5, 2017
873
288
0
Ride
07 335i MT
Grease was used. Same result :(

Possibly not enough? Other than that the gap would have to be tighter then.
I guess think of it like this, no matter what you do the path across the gap has to be the least resistance
 

335i_nick

Specialist
May 10, 2017
98
43
0
Ride
335i
Possibly not enough? Other than that the gap would have to be tighter then.
I guess think of it like this, no matter what you do the path across the gap has to be the least resistance

I am removing the plugs now to check if this has happened to a 3rd set of plugs. I don't have any more on hand right now. If they are not carbon tracked I am going to reduce the gap to .022" and see if that helps.

Thanks for the help sir
 

Bmwfixerguy1

Lieutenant
Jun 5, 2017
873
288
0
Ride
07 335i MT
I am removing the plugs now to check if this has happened to a 3rd set of plugs. I don't have any more on hand right now. If they are not carbon tracked I am going to reduce the gap to .022" and see if that helps.

Thanks for the help sir

Yes definitely reduce the gap a little and see.. What gap are the current plugs at again? Also when you are gapping them what tool are you using to gap with?
Feeler gauge or round wire gauge are best.. Those little key chain ones at check out at you local advanced pep zone are a huge no no! .030 on one of them could easily be .035 which would then be cause of problems
 

335i_nick

Specialist
May 10, 2017
98
43
0
Ride
335i
Yes definitely reduce the gap a little and see.. What gap are the current plugs at again? Also when you are gapping them what tool are you using to gap with?
Feeler gauge or round wire gauge are best.. Those little key chain ones at check out at you local advanced pep zone are a huge no no! .030 on one of them could easily be .035 which would then be cause of problems

Using a feeler gauge. It's gapped at .025" at the moment. Going to .022"
 

335i_nick

Specialist
May 10, 2017
98
43
0
Ride
335i
Here's all 6. No carbon tracking. But still misfiring so I'm gonna go ahead and lower the gap. Making progress!
 

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