Limp Mode please help! Only getting misfire codes nothing else

[Lexshive]

its an 08 e90 6mt that i cant seem to shake this ongoing issue of limp mode check engine lights and eating spark plugs. so this is what ive compiled from owning this for a year and chasing this ongoing gremlin in it. The car at 8000 rpms (when it was running fine no issues going on) would lean out cylinder 5 then crunch the diodes on the spark plug together into the center of the plug. Then cylinders 6 & 7 were black and wet on the plugs when i pulled spark plugs. Bank 1 plugs all look great consistent color no problems. I get misfire codes only for cylinders 5-8 sometimes a cylinder on bank 2 would come up on the scan but i think once it misfires on so many cylinders on the other bank its just domino effect. Im basing more of this on what ive actually found by pulling plugs. The car is consistently going into limp mode now after 10 minutes after each start up. I can shut the car off and drive it again for another 10 minutes with no issues runs fine before it goes into limp mode. Seems like when it goes into limp mode it will run rough for about a minute and then evens itself out and seems to run on all cylinders again still in limp mode. The car is stock stock other than a cut out exhaust kit installed right before the tail muffler box. Ive replaced a bank 2 o2 sensor pre cat and a fuel pressure sensor on the firewall trying to chase this. The thing that doesnt make sense to me is I only get misfire codes nothing for throttle actuator codes or injector codes which is more the way im leaning. Ive had a couple bmw mastertechs scratching their heads. Any insite id love to get this thing running smooth and consistent without the worry of my car going into limp mode or eating a spark plug every time a corvette pulls up revving. Im happy to answer more questions and details to help aide in opinions. Im lost and loosing "the fun factor" of this car after the bmw oil and gas tax with the headaches and down time with it. Hook me up guys this car needs to get back on the road!

[BOOF-M3]

Have you been to a dealership to have them look at it? And if so what have they said?

[mmbv1000]

I think I’ve got the same thing going on - started a thread here too. I had my rod bearings replaced back in Jan. A couple weeks after I got misfires on cylinder 2 so had the coil replaced and throttle actuators done as well since this had been an ongoing issue.

Car ran fine for several months then just a few weeks ago got CEL while on the freeway. Light went out on it’s own but then got misfires and codes a week later. Misfires on all remaining 7 cylinders. It was odd they all went at the same time and #2 was good... led me to believe it was just time to replace them so had that done. Unfortunately this didn’t fix he issue and I stalled a day later. Took the car to BMW this time and they said hey found a loose ground wire under one of the coils and thought the dme was compromised as a result. We replaced it (even though I doubted them) and it didn’t work so now I have them fixing their misdiagnosis.

At this point I’ve had rod bearings, both actuators, all 8 coils and plugs, and the dme replaced. No luck. In my thread someone responded they’ve seen issues like this coming from a faulty fuel valve under the manifold or bad ICV... more likely the valve. I’ve mentioned this to BMW but they haven’t pinpointed that yet. Someone else responded they’ve had issues like this in the past resulting from a loose connection on a wire harness. I’m leaning towards this being an electrical issue but haven’t solved it. I’ve been without a car for several weeks and the BMW techs (master techs too) are puzzled.

[Ipson]

Got the same thing going on with my '11 E93. Runs fine in the morning or after sitting for a long period of time, but shut it off and then try to start it and the dash lights up with full limp mode. Seems like I am chasing a ghost. No one on any of the threads has been able to pinpoint the problem. I'm very interested to hear what others have done to eradicate this ghost, because it is taking the fun out of driving it.

[Tewie]

Is there something leaking down on to the plugs? Oil?

[sixspeedm3]

sorry to revive an old thread, but did you ever figure out what it was ? i have a 2011, 6spd m3, changed icv, lfps, dme, checked injectors, coils, sparks, and changed 02 sensors, compression test, leak down test, valve springs are good, actuators both replaced.... smh. I'm at a LOSS.

[dpaul]

Originally Posted by jamesS65

sorry to revive an old thread, but did you ever figure out what it was ? i have a 2011, 6spd m3, changed icv, lfps, dme, checked injectors, coils, sparks, and changed 02 sensors, compression test, leak down test, valve springs are good, actuators both replaced.... smh. I'm at a LOSS.

What exactly are your symptoms? Be as explicit as possible.