[TwinCoupes]

Hi everybody I've had my 2008 E92 335xi for about 4 months and it's been great up until a few days ago. I came out In the morning on one of our beautiful Canadian mornings and it was -23 degrees Celsius out and when I started my car it had a really rough idle and had a hard time staying running. So I thought it might be the cold so I tried to let it warm up for about 30 mins but still no change and at this point I had no check engine lights or messages so I tried to take it out for drive and see if anything would change. I made it about 5 blocks then the check engine light started flashing and then the reduced engine power message came up along with the traction control light, the yellow brake light, and the 4x4 messages with the yellow triangle and arrow around it. So after all that i limped the car back home. I had a friend take a look at the codes and the were current codes P0303, P0302, P0300, P0301, P2414, P323F, B2AAA, and pending code P0140. It was a lot so I replaced the bank 1 sensor 1 O2 sensor and spark plugs because they were fouled with fuel and all black thinking that would solve the problem but still the first 3 cylinders all bank 1 were misfiring and the car is still running like shit. I've swapped around the coils from the first bank to the second and the coils all seem to be fine. I made sure I changed the right O2 sensor. I've cleared the codes with my jb4 multiple times disconnected the battery and made sure all the connectors that I touched were all firmly in place but it's still not firing any of the cylinders on the first bank and now I'm kinda stuck wondering what to do next and I here looking to see if anybody here had any advice on what I should do next thanks.

[Jeff@TopGearSolutions]

Check the plugs again for fouling, it could be an indication of a leaky injector.

If all the plugs are good and coil packs are new then the only thing really left is fuel or valve cover gasket leaking oil on the spark plugs.

How old is your battery and is your battery weak?

[TwinCoupes]

Originally Posted by Jeff@TopGearSolutions

Check the plugs again for fouling, it could be an indication of a leaky injector.

If all the plugs are good and coil packs are new then the only thing really left is fuel or valve cover gasket leaking oil on the spark plugs.

How old is your battery and is your battery weak?

So yesterday I checked to make sure I'm getting spark to the bank 1 cylinders (1-2-3) which have the misfire issue and they were all sparking fine. The battery should be strong I've sat in parking lots with music and rest mode for the ax on and no battery issues. I moved on to testing if the injectors were the issue so I swapped the injectors from bank 1 over to bank 2 and the misfire still was happening over on bank 1 with bank 2 still firing fine so I believe that means the injectors are not the issue. I'm really confused now because it's not a spark issue or the injectors but the cylinders 1-2-3 are still misfiring. Would the HPFP only cause 3 cylinders to misfire and not all of them or could this be just an electronic issue that resetting with bmw coding tools would fix because that's where I'm at now I'm not sure what else to check and replace.

[924er]

Originally Posted by TwinCoupes

So yesterday I checked to make sure I'm getting spark to the bank 1 cylinders (1-2-3) which have the misfire issue and they were all sparking fine. The battery should be strong I've sat in parking lots with music and rest mode for the ax on and no battery issues. I moved on to testing if the injectors were the issue so I swapped the injectors from bank 1 over to bank 2 and the misfire still was happening over on bank 1 with bank 2 still firing fine so I believe that means the injectors are not the issue. I'm really confused now because it's not a spark issue or the injectors but the cylinders 1-2-3 are still misfiring. Would the HPFP only cause 3 cylinders to misfire and not all of them or could this be just an electronic issue that resetting with bmw coding tools would fix because that's where I'm at now I'm not sure what else to check and replace.

dude im pretty sure its one of your o2 sensors that failed. common when you are misfiring all on one bank. it even showed a code for o2 sensor, which was the biggest give away. I might be wrong tho. good luck and report back here with results

[Jklad]

Check the thread on here on the fried dme, if you have an msd80 Ecu (2007 and early 2008) this could be a possibility.

[Digitalism]

He says in his OP that he replaced the O2 sensor.

I was thinking maybe the injector MOSFETS/transistors as well.

But usually it relates to a code as well.

[TwinCoupes]

So I got the problem figured out my DME had 3 fried MOSFET's so I just order 6 upgraded chips and had a tv repair shop solder them on so I'm back on the road again for now...

[Morpheus]

So you didn't have the DME error like in Roy cormier's case? And you found these were bad?

[jskin1510]

Originally Posted by TwinCoupes

So I got the problem figured out my DME had 3 fried MOSFET's so I just order 6 upgraded chips and had a tv repair shop solder them on so I'm back on the road again for now...

I started this thread and I'm starting to think I have the same issue:

http://www.e90post.com/forums/showth...ighlight=b2aaa

How did you come to the conclusion that it was these "MOSFET's" and/or transistors? where and how do you know which ones to get? Also if I need to research locally for a place that would be able to replace these in the DME... should I just look up "tv repair shops" and see from there?

Haven't even driven car since this came up about a week and half ago and good thing I haven't sold my prior car yet but really need to get this figured out asap. thanks.