|
|
11-18-2022, 11:18 AM | #1 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Misfire -- Incorrect Spark plugs
Here is an FYI that I couldn't find too much research on. Upon doing typical "tune-up" maintenance on my E93 M3, I decided to change the spark plugs. There was a historic issue with a misfire on cyl #3 and #5.
The spark plugs I chose at the time were the new NGK Ruthenium spark plugs--which were listed under NGK's website as being compatible. Long story, short...these Ruthenium plugs are NOT compatible with S65 "ion-sensing" ignition. ONLY the platinum NGK plugs are compatible as the "ion-sensing" is tuned for this dual ground electrode plug. |
11-18-2022, 11:38 AM | #3 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
One way to verify this is to utilize ISTA and look at the ignition "quality" panel when doing a cold start and when the symptom is presenting itself.
Here is the definition via ISTA when looking at a very nice graph showing the burn quality. This can be immensely helpful when dealing with a "cold-start only misfire." We see our values are from "0" to almost "3" and should expect a value in between. |
Appreciate
1
DrFerry6722.50 |
11-18-2022, 11:41 AM | #4 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Running with Ruthenium NGKs
Here is what the graph was showing with running all 8 Ruthenium spark plugs using the ISTA routine.
The car was not at all happy with running, misfire every cylinder and then somehow magically running on 4 cylinders of two from each bank. |
Appreciate
1
DrFerry6722.50 |
11-18-2022, 11:44 AM | #5 |
Lieutenant Colonel
1423
Rep 1,629
Posts |
im more curious as you why you even tried to sway from the recommended spark plugs
__________________
|
Appreciate
0
|
11-18-2022, 11:47 AM | #6 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Platinum NGK Plugs Graph
Then I had to painstakingly change out ALL the spark plugs again for the proper Platinum NGKs that I bought brand new.
Here you can see the graph looks perhaps a little different--but the DME was noticeably happier as none of the cylinders were deactivated. |
Appreciate
1
DrFerry6722.50 |
11-18-2022, 11:57 AM | #7 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Now my whole point for doing this was to chase a very intermittent mis-fire and to upgrade the plugs to something that would last longer than 37k miles change intervals.
This misfire I was chasing ONLY seemed to happen on cold starts, medium acceleration around 1500 rpms. Here is a graph with the Platinum plugs AND a very cold-start. At this time, I switched the coil from cylinder #3 to #1 and then #5 to #6. |
Appreciate
1
DrFerry6722.50 |
11-18-2022, 12:01 PM | #8 |
Lieutenant General
5179
Rep 10,555
Posts |
If you had searched, you would have found posts from years ago about ruthenium plugs not working…. These cars use ionic knock sensing, which means sensing through the plugs rather than sensors mounted to the block.
|
Appreciate
1
DrFerry6722.50 |
11-18-2022, 12:05 PM | #9 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Cyl 1 Coil -- Low Performance
As the car warms up, we start to see a stark difference with the graphs, thus, pointing towards an issue with the coil. At this point, it is also POSSIBLE to see that cyl 7 is on it's way out as well.
|
Appreciate
1
DrFerry6722.50 |
11-18-2022, 01:00 PM | #10 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Yeah...it did kind of suck. But at this point, I have the right plugs in the motor, and now I feel very confident on changing them out--since cyl 4 and 8 are THEE worst to get to.
|
Appreciate
1
DrFerry6722.50 |
11-18-2022, 01:19 PM | #12 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
To put it short, the NGK Platinum plugs are tuned *calibrated* with the ion sensing strategy of the car. The S65 engines do not have knock-sensors, thus, utilize a different method.
Upon searching the forum, I couldn't find anyone who did an in-depth review with actually utilizing dealer SW to measure and observe the misfire. In addition, there is a panel in INPA to measure quality, but it is def not as user friendly as a printed graph of data. So hopefully this helps someone out if they are chasing an intermittent mis-fire (with of course using the correct plugs) that doesn't always present itself with a fault code. Using ISTA can be of great help in determining this. P.S. Since I'm fairly confident the coil on cyl #1 is failing by means of swapping coils, I went ahead and ordered a coil to replace. Once that is in, I'll see if any more intermittent misfires come and go. |
Appreciate
1
DrFerry6722.50 |
11-18-2022, 03:33 PM | #13 |
Major
1540
Rep 1,076
Posts
Drives: 2009 E92 M3 Dakar Yellow II
Join Date: Oct 2021
Location: Edmonds, WA
|
I hope you were able to source genuine BMW coil for a reasonable price. We're finding "equivalent" coils from recognized OE brands are failing and there are lots of counterfeit coils in circulation.
|
Appreciate
2
RocketyMan223.00 DrFerry6722.50 |
11-18-2022, 03:46 PM | #14 | |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
Quote:
I would like to know who the OE supplier is for the coil. Is it NGK, Bosch? It also seems like there is an "LCI" version of the coil which might prove to be more reliable and durable...? |
|
Appreciate
1
DrFerry6722.50 |
11-18-2022, 04:34 PM | #16 |
First Lieutenant
223
Rep 333
Posts
Drives: E53 X5, E83 X3, E93 M3
Join Date: Nov 2022
Location: PNW
|
There's two different P/N for the pre- and LCI engines...
The 12137838388 was the first iteration. The 12137841754 is the notable one that has the springy contacts on the tube. From my research there is a NGK and BOSCH version of the plug. These seem really hard to find and are on national backorder. NGK U5118 BOSCH 12137841754 |
Appreciate
0
|
Post Reply |
Bookmarks |
Thread Tools | Search this Thread |
|
|