Precision Raceworks coil failure?

[Ztuck45]

I’m looking for some insight. I recently developed a cylinder 6 and 5 misfire. Cylinder 6 was intermittent under load and cylinder 5 started misfiring intermittently as well but eventually became a constant misfire (Even at idle). I just started running full e85 after installing a double shotgun kit.

Upon investigation i found some carbon tracking on cylinder 6, so i replaced that plug. Cylinder 5 plug looked fine so i replaced that plug anyway and swapped the precision coil to cylinder one.

After doing this the misfire moved to cylinder 1, which made me believe a coil failed.

So my question is, has anyone had a precision coil fail? If so is there a reason why it failed or just coincidence?

 

[135boost]

i have these PR coils too and got misfires
-CG turbos
-E85
-27 psi boost
-DB shotsun so DI only

i regapped plugs until that misfire was gone, started from .25
-low boost on a range under 10 psi ok, 20 psi misfire in all cylinders.
first search for problem in LFPF or HFPF or tune
cause that misfire trigs lean condition warning and skyrocketing
lambda to 20
then discussion with trebila(wery helpful guy) and he told it`s misfire issue
dropped to .20
- medium boost ok, 20 psi ok, misfires at 27 psi
dropped to then to .16
-seems to work with even that moderate 27 psi
but i get random misfires at criusing speed, not so ofen
but few times a day or so.

 

[buster84]

i have these PR coils too and got misfires
-CG turbos
-E85
-27 psi boost
-DB shotsun so DI only

i regapped plugs until that misfire was gone, started from .25
-low boost on a range under 10 psi ok, 20 psi misfire in all cylinders.
first search for problem in LFPF or HFPF or tune
cause that misfire trigs lean condition warning and skyrocketing
lambda to 20
then discussion with trebila(wery helpful guy) and he told it`s misfire issue
dropped to .20
- medium boost ok, 20 psi ok, misfires at 27 psi
dropped to then to .16
-seems to work with even that moderate 27 psi
but i get random misfires at criusing speed, not so ofen
but few times a day or so.

Maybe you have a bad set, or your wiring isn't correct?

I ran my gcs (1.0's) and ran 28-29psi taped at the top end with stock coils, .20 gap and no misfires on e85 and Tuned by trebia and I'm running port injection with the jb4.

 

[135boost]

Maybe you have a bad set, or your wiring isn't correct?

I ran my gcs (1.0's) and ran 28-29psi taped at the top end with stock coils, .20 gap and no misfires on e85 and Tuned by trebia and I'm running port injection with the jb4.

There can be some differences beween port injection and DI only cause DI injector is sitting quite near plug and
on injection cycle there is for sure a time in combustion chamber after injection cycle is injected where a/f ratio is not homogen but it`s very rich close to spark plug caused on that plug/injector position sitting near each other and before
fuel has time to spread in entire combustion chamber and that maybe cause spark to be harder to iginite.

on port injection, the AF ratio is homogen when it arrive chamber and that maybe do the difference.
i think wiring is correct and i have a not so bad set cause that .16 seems to solve whole problem

my 1 cent

 

[buster84]

There can be some differences beween port injection and DI only cause DI injector is sitting quite near plug and
on injection cycle there is for sure a time in combustion chamber after injection cycle is injected where a/f ratio is not homogen but it`s very rich close to spark plug caused on that plug/injector position sitting near each other and before
fuel has time to spread in entire combustion chamber and that maybe cause spark to be harder to iginite.

on port injection, the AF ratio is homogen when it arrive chamber and that maybe do the difference.
i think wiring is correct and i have a not so bad set cause that .16 seems to solve whole problem

my 1 cent

That's possible too.

I'd double check everything. Check the wiring, look for damage on the coils, boots, and spark plugs (make sure the insulators are good). Then swap the coils from a non missfire cylinder with one that is and see if it follows, if not swap the boot over, then if it still doesn't move swap the plugs.

You might have a bad coil or boot or a broken plug. Your just going to have to use the process of elimination with this issue to figure it out. Your gap shouldn't need to be anywhere near as low as you dropped it to work otherwise you might as well use stock coils.

https://bmw.spoolstreet.com/threads/misfire-issues-with-precision-coils.1973/

 

[135boost]

That's possible too.

I'd double check everything. Check the wiring, look for damage on the coils, boots, and spark plugs (make sure the insulators are good). Then swap the coils from a non missfire cylinder with one that is and see if it follows, if not swap the boot over, then if it still doesn't move swap the plugs.

You might have a bad coil or boot or a broken plug. Your just going to have to use the process of elimination with this issue to figure it out. Your gap shouldn't need to be anywhere near as low as you dropped it to work otherwise you might as well use stock coils.

https://bmw.spoolstreet.com/threads/misfire-issues-with-precision-coils.1973/

i agree with that, it should work with bigger spark gap but i doubt it`s faulty
parts or wiring cause on .025 gap i got misfire in almost every cylinder, 5 out of 6.
i have those 95770 plugs, that can be part of issue to get that misfire, on my undestand
they should work well but this is a sum of DI only/ high boost/ e85 / 95770 / pr coil
so pinpoint of problem is hit and miss. suggestion of spark plugs is to be taken here.

on mhd, there is tagged that PR coil option.

full throttle power seems to be decent on this setup but i have a issue on steady cruising
ignition advance and some strange oscillating on power at 2000-2500rpm range what we are solving
with trebila.

 

[buster84]

i agree with that, it should work with bigger spark gap but i doubt it`s faulty
parts or wiring cause on .025 gap i got misfire in almost every cylinder, 5 out of 6.
i have those 95770 plugs, that can be part of issue to get that misfire, on my undestand
they should work well but this is a sum of DI only/ high boost/ e85 / 95770 / pr coil
so pinpoint of problem is hit and miss. suggestion of spark plugs is to be taken here.

on mhd, there is tagged that PR coil option.

full throttle power seems to be decent on this setup but i have a issue on steady cruising
ignition advance and some strange oscillating on power at 2000-2500rpm range what we are solving
with trebila.

hmm. Where did you buy your spark plugs? I saw this post about fake ones and it made me think about how this could cause a problem like your having since its happening on all cylnders. If you trust where you bought them this isnt the problem.

http://f80.bimmerpost.com/forums/showthread.php?t=1468550

 

[chadillac2000]

Just curious, for all the people running aftermarket coils, were you having issues with stock coils?

Most of these upgrades seem to create more problems than they solve...

 

[Jeffman]

We have also released new tables to MHD a few months back and are still waiting on them to push the new tables out in an update to MHD. This will give even more power out of our ignition kits then they currently have which is already the highest output coil on the market and will now push even further.

Maybe I missed the announcement, but have the new ignition tables mentioned above been incorporated yet into MHD or the new XDF released by Jake Y?

 

[Promodracer]

Maybe using

Alex,
Thanks for the post!

Alex is correct, this is the most common issue we have found in this kit. To date with 1,000's of coils on the market now there have been zero natural coil failures. The only failures have been due to shorts in wiring into the factory harness, or not matching the wire colors. We have OEM quality connectors coming very soon to address this issue head on (it has been low failure rate but it will make install much easier too).

We are looking at changing the design for the plug wires and are looking at a couple different manufacturing options. The wires work perfectly fine but we have found that the current generation of enthusiast have very little experience with plug wires. So we are looking to develop plug wires that are easier to install so there are less issues as a result of improper seating of the wires. Don't expect these until Q3-Q4 of this year.

We have also released new tables to MHD a few months back and are still waiting on them to push the new tables out in an update to MHD. This will give even more power out of our ignition kits then they currently have which is already the highest output coil on the market and will now push even further.

wires from msd may be in order as they can withstand 44amp magneto's. great stuff. Use them on Alcohol car.

 

[Promodracer]

i have these PR coils too and got misfires
-CG turbos
-E85
-27 psi boost
-DB shotsun so DI only

i regapped plugs until that misfire was gone, started from .25
-low boost on a range under 10 psi ok, 20 psi misfire in all cylinders.
first search for problem in LFPF or HFPF or tune
cause that misfire trigs lean condition warning and skyrocketing
lambda to 20
then discussion with trebila(wery helpful guy) and he told it`s misfire issue
dropped to .20
- medium boost ok, 20 psi ok, misfires at 27 psi
dropped to then to .16
-seems to work with even that moderate 27 psi
but i get random misfires at criusing speed, not so ofen
but few times a day or so.

I would consider .018"

 

[Rcboosted2007]

I had misfires right off the go with these coils.from the first day i had misfires on random cylinders.I then ordered the new style boots and had the same problem.Then a blown mosfet. Once fixed,after two pulls i lost a cylinder.