Misfire Cylinder 2,3,5,6 / Lean Bank 1&2 *Help*
 

My wife's Z3 3.0 has been garaged for a few days while hurricane Sandy came through. Today the weather cleared up and she decided to run a few errands. During this time the car ran rough during idle to the point of almost stalling out. I assumed it was due to sitting for a few days and the cold weather.

The CEL was on, so during my test drive I stopped at a local auto store and used their code scanner. So this is what I got:

P0300 Multiple Misfire Detected
P1345 Misfire Cylinder 2 With Fuel Cut-off
P1347 Misfire Cylinder 3 With Fuel Cut-off
P1351 Misfire Cylinder 5 With Fuel Cut-off
P1353 Misfire Cylinder 6 With Fuel Cut-off
P0171 Fuel System Too Lean (Bank 1)
P0174 Fuel System Too Lean (Bank 2)

I read that the lean condition could be a leak in a vacuum line, but which vacuum line.
Any idea on how to troubleshoot the misfire?

Thanks in advance!

I was told that a bad/dirty MAF sensor will make a code for a lean condition on both banks. I have cleaned the MAF sensor.

I'm currently in the middle of changing the spark plugs, but ran into a serious problem. One of the spark plugs doesn't want to come out. I think whoever changed the spark plugs last cross threaded the plug. It's a bitch trying to take it out so do I keep on trying or try to tighten it back?

I guess the spark plug was just seized. I put some PB blaster down there and let it soak for about 20 mins, then used my breaker bar and slowly put some torque on it. The car seems to be running smoother. The CEL has been reset, fingers crossed.

The CEL came on again today, but only got 1 code:

P0171 Fuel System Too Lean (Bank 1)

So I'm assuming by just replacing the spark plugs I was able to correct the misfire on cylinders 2, 3, 5, & 6.

Now I have to figure out how to fix the Lean on bank 1.

I think there might be a problem with the DISA valve. After work today, I'm going to do some troubleshooting on the DISA. Found out you can just replace the worn parts for $75 instead of buying a brand new DISA for $200.

Link to DISA repair kit http://germanautosolutions.com/DISA_...epair_Kit.html

Miss fire/lean mix
 

Has anyone thought to check the fuel filter? Just thinking out loud-Good luck-Gnatthecat

Fill her up with premium and a good fuel system cleaner and take her out on the highway and dog her a little bit. Blow some carbon out. Keep those revs up a while to really clean her out good. Good luck.

Having the same problem. I would be very interested to see if you can fix the problem.

I filled her up with Shell 93 octane and added some Seafoam to the fuel tank. While doing some spirited driving on the highway the CEL went off. So looks like she good to go now.

Hey bna1dew check this link out very informative http://forum.e46fanatics.com/showthread.php?t=897616

So I only replaced the spark plugs, cleaned MAF sensor, added Seafoam to fuel, and inspected my DISA valve. I started off with the cheap, easy items before attacking more high dollar items that probably wouldn't do anything but make my pockets lighter. Total spent on this fix $50 and 2 man hours.

I used promo code DOTW44 at advanceauto.com to get 25% off on the spark plugs and picked them up at the store. (note: the number 44 is the number of the week, so next week it will be 45 and so on.)

OP did the car want to start? MY 2001 325ci has the same misfires in each cylinder but will not start.

The car started no problem, but the idle was real rough the whole car was shaking and it was still drivable. I guess I lucked out and it was just the spark plugs that went bad.

The misfires cause rough idle I don't think it will prevent your car from starting. Have you checked the battery, car needs 12.6 volts to start not just 12 volts.

How do you clean the MAF sensor?