03 325xi coding P0313 and P1345

Hey all,

I was hoping I could get some insight from you all regarding something my 2003 325xi has been up to lately.

This sunday I drove from Pennsylvania to my house in Maryland, the drive went fine, no problems. I was pretty much out of gas by the time I got home but I work a mile from where I live so I decided I could get by for a day with my gas light on.

When I woke up on monday to drive to work my car started fine. I pulled out of my complex and when I came to a stop my car shuddered and the check engine soon light came on. From that point until work the car ran terribly, sounded like a cylinder was misfiring or something. On my lunch break I started it up and the light was still on but the car ran without any problems. So I brought the car to autozone and this lady checked it out, said that her tool couldn't find any engine codes. My guess is she might not have known how to properly work it, just speculating. Anyway, the check engine soon light is still on at this point, after she hooked up to the car and didn't find any codes.

Fast forward to tuesday morning, I start the car, the check engine soon light is off, then when I come to stop the car shudders, drops rpms, then the light comes up and the car runs like crap. Come my lunch break, the car works fine. Light still on. I drove to the gas station and put half a tank of 89 in. I'm ashamed to say that the last time I filled it I put in 87.

So I went to autozone today after work and these two codes come up

P0313 - PCM has determined a misfire has occurred with low fuel

P1345 - A misfire on cylinder 2 with fuel cut off

The check engine soon light was cleared after the autozone employee disconnected the device. This confuses me because it wasn't cleared when the previous employee who checked my card hooked up to the vehicle.

Since then, the car has run fine. At this point I'm thinking to myself I might have just been tragically low on gas and that combined with the cold caused the ol' 325xi to act up.

I've read the other posts that come up on google e46 forums/bimmerfest etc and it seems like people suggest it might be the coils or sparks. As I said before I'm trying to convince myself that I was so low on gas that maybe my engine wasn't getting enough fuel to run itself properly.

I would appreciate it greatly if someone here would be kind enough to tell me what they think.

Thanks for reading guys, happy driving.

A fuel issue would usually create a misfire on multiple cylinders, as would intake leaks. Fill with 93oct to eliminate this as a possibility--you're wasting money buying 89. You're also risking your fuel pump by running low on fuel, because the fuel cools the pump motor. Best to not do that, and use the proper fuel.

If the problem continues to recur, it probably is a coil or plugs. You don't mention mileage, but if you haven't changed the plugs they're probably original and long overdue for replacement. If that doesn't fix it, you can swap the #1 and #2 coils and see if the misfire codes follow the suspect coil (ie. it throws a p1344 or whatever cyl 1 misfire is). You can also test the pressure at the fuel rail to make sure the pump isn't getting weak, but based on your description, that doesn't seem too likely to me.

The light is clearing because the misfire is intermittent. After a certain number of cycles (driving cycles, rpms, whatever), the computer clears the fault. If it stays off, don't worry about it and fill up before the light comes on.

Coleman,

Thanks for the reply. Will do with the 93. If it continues to f with me i'll do a coil check.

Read the first 2 links below in my signature.

Also read this thread - http://forum.e46fanatics.com/showthr...ghlight=report

Usually when misfires occur the CEL will come on immediately. Try turning the engine off and restart it and they should clean if they are misfires with fuel cut off.

This is not a solution, just a way to make the car more driveable.

Learn about the Hidden OBC functions.

Try unplugging coil for cylinder 2 while car is running and try to listen to see if the engine is acting any different. I never listened to an autozone scanner because it picks up codes in my car that arent even picked up by my BMW specific scanner.