Engine Malfunction - P2307

[dreamcast731]

Hey guys,

I have a 2013 BMW M3 with 37,900 miles.
Spark plugs were done on 12/14/2018 at 28,567 miles.

Last night after dinner, I pulled out of the parking lot and was slowly approaching the traffic light, and I felt the engine shake a little bit, and then I get this "Engine Malfunction" message along with the half engine sign on the dash, but no other lights or other error messages. Engine speed have been limited to 4.5k rpm and the engine idle is about 500 rpm higher than usual. I was able to drive home in limp mode, but I couldn't pull the codes right way and had shut down the car.

About 1 hour later, I was able to check on the car, the car started absolutely fine, everything was back to normal, no "Engine Malfunction" message or half engine on the dash anymore, but I was able to pull a P2307 code from the OBD.

So today, the car started up normal, everything was normal, even reved it all the way out for a couple times, drove for about 20 miles / 45 minutes today and I couldn't replicate the error message to pull the codes while the error message is present. The P2307 code is gone/cleared on it's own today, there were no error codes found on the OBD reader.

Any idea what was the cause of the "Engine Malfunction" message from last night? Please advise, thank you!

[BlueberryM3]

Did you ever figure it out OP? The same issue happened to me last night. I pulled codes P2304 and P2307 (ignition coil b and c, primary circuit - circuit high)

[dreamcast731]

Originally Posted by BlueberryM3

Did you ever figure it out OP? The same issue happened to me last night. I pulled codes P2304 and P2307 (ignition coil b and c, primary circuit - circuit high)

Hey there, sorry, I don't check the forums.... here's what another member sent me last year:

"Is this the e92 m3 v8? If so it was the shared coil ground loose on the rear of the valve cover. Even though that ground is for all 4 coils on that bank it was only setting cyl 3.

It was very intermittent. Randomly it was a hard misfire and basically that half of the engine was shutting off all 4 cylinders.

If that isn’t it try swapping coils. Swapping plugs. Use a scope or test light to make the you have computer control on that coil. Check injector pulse. Compression. Leakdown test. Etc etc"

So my shop checked that and the grounding cable for the engine and replaced the cables. Problem was gone for almost a year / 2k miles, but it's back.....

Did you ever figured out what your cause is and your solution???

[BlueberryM3]

Originally Posted by dreamcast731

Hey there, sorry, I don't check the forums.... here's what another member sent me last year:

"Is this the e92 m3 v8? If so it was the shared coil ground loose on the rear of the valve cover. Even though that ground is for all 4 coils on that bank it was only setting cyl 3.

It was very intermittent. Randomly it was a hard misfire and basically that half of the engine was shutting off all 4 cylinders.

If that isn’t it try swapping coils. Swapping plugs. Use a scope or test light to make the you have computer control on that coil. Check injector pulse. Compression. Leakdown test. Etc etc"

So my shop checked that and the grounding cable for the engine and replaced the cables. Problem was gone for almost a year / 2k miles, but it's back.....

Did you ever figured out what your cause is and your solution???

Yes I did solve my issue! It turned out to be a loose grounding cable. I haven’t had any issues since.

[dreamcast731]

Originally Posted by BlueberryM3

Yes I did solve my issue! It turned out to be a loose grounding cable. I haven’t had any issues since.

Cool, thanks for the reply!