06 X5 3.0 Code PO302 PO303 PO 305 and PO300 Misfire

[PalmSpringsE534.6]

Originally Posted by FREE100KSECRET

Thanks, I only wish I had more specific BMW code reader. Bought the IMPA disc, but have yet to find an old XP laptop to install it on. Live and learn, will be more specific in the future.

You can install INPA on Windows 10 (run it in Compatability Mode). . I have INPA on my MacBook Pro with Parallels running Win10. No issues except that when you plug in the DCAN cable to the USB port, Parallels will ask if you want to connect it to MacOS or to Windows.

[FREE100KSECRET]

Originally Posted by PalmSpringsE534.6

You can install INPA on Windows 10 (run it in Compatability Mode). . I have INPA on my MacBook Pro with Parallels running Win10. No issues except that when you plug in the DCAN cable to the USB port, Parallels will ask if you want to connect it to MacOS or to Windows.

Thanks a million, never heard that before, and always wondered why all these companies who sell the INPA always say works only on XP, and here I have been sitting on this issue for months, so thank you, not being a computer person, is Parallels a program that also must be downloaded, never heard of it? Thanks again, I appreciate it.

I have looked into it and since I don't have a mac, which is what it is used on to install win 10, I was wondering if it is also needed when you are not using a mac laptop?

[PalmSpringsE534.6]

Originally Posted by FREE100KSECRET

Thanks a million, never heard that before, and always wondered why all these companies who sell the INPA always say works only on XP, and here I have been sitting on this issue for months, so thank you, not being a computer person, is Parallels a program that also must be downloaded, never heard of it? Thanks again, I appreciate it.

I have looked into it and since I don't have a mac, which is what it is used on to install win 10, I was wondering if it is also needed when you are not using a mac laptop?

Parallels is only needed on a Mac to allow it to easily run Windows on demand. If you are not on a Mac...no need for it.

[X5chemist]

An experienced mechanic knows those code by heart.
Did you pull the plug? I've seen individual plugs fail. You can move the coil pack to another location or ohm it with a voltmeter. Compare ohm reading between coil packs. You can do the same for fuel injectors. One cylinder miss fire will cause other cylinders to misfire even though other cylinders may be okay. The P0303 is where I would look the most for troubleshooting. MAF and air intake leaks are very common causes.

[FREE100KSECRET]

Originally Posted by X5chemist

An experienced mechanic knows those code by heart.
Did you pull the plug? I've seen individual plugs fail. You can move the coil pack to another location or ohm it with a voltmeter. Compare ohm reading between coil packs. You can do the same for fuel injectors. One cylinder miss fire will cause other cylinders to misfire even though other cylinders may be okay. The P0303 is where I would look the most for troubleshooting. MAF and air intake leaks are very common causes.

Thanks, have owned a dozen BMW's over the years, and I went by the misfire injector open issue, so ordered an injector seeing that it was specific code, but I will double check coil anyhow while I check further. Given one cylinder misfire can impact others, will check the original #3 injector and replace, but while I have fuel rail off, will check the other injectors to see what the readings are. So thanks again, never had this issue in all the years working on these BMW's.

[crystalworks]

Originally Posted by X5chemist

An experienced mechanic knows those code by heart.

I absolutely agree any pro mechanic working on many brands would.should know them by heart. My exception those who, like me (and probably many of any BMW forums members) who are not pros, only work on BMWs, and were forced to buy a BMW specific tool a long time ago. So P codes haven't been seen in a LONG time (at least 10 years and as many BMWs in my case).

Sorry OP for the slight OT. But your misfire situation is definitely one all of us have gone through at some point on a BMW. It's usually vacuum related but at times can be ignition system (least probably in my experience is fuel supply). If you have access, your short term and long term fuel trim data would be helpful with diagnose by some of the more technically minded members.

When I have misfires, especially at certain mileages, I tend to take the shotgun approach to it and replace all coils/plugs, vacuum lines, crank case breather components, valve cover gaskets, etc, etc. It usually costs more (sometimes a lot more) but saves time on diagnosis and "resets" the clock for another ~100k miles before I'll need to worry about misfires again.

[FREE100KSECRET]

Thanks, I will start checking for the issue, just thought someone would have had exact same issue, not just random misfires, but specific 2.33 and 4 injector circuits. Will check further and post results.

[cn90]

Multiple misfire codes:

- Air leak, check again and again.

- Bad ignition coil, but usually just 1-2 bad coils.

- Spark Plugs getting old...

- Bad gasoline (contaminated with water).

[FREE100KSECRET]

Originally Posted by cn90

Multiple misfire codes:

- Air leak, check again and again.

- Bad ignition coil, but usually just 1-2 bad coils.

- Spark Plugs getting old...

- Bad gasoline (contaminated with water).

Thanks, thought about gas as a friend just had that issue given so much rain in area, gas station tanks may have been leaking in water. Put Heet in tank just in case, not change. Engine will start, but will not accelerate normally, so with 4 cylinders suddenly throwing codes, and it was running great, I am stumped. Checked for vacuum leaks, intake manifold ports sprayed with starter fluid to see if any change. No luck, problem started with just #3 with open injector circuit and misfire and only occasionally, so I put in injector cleaner in tank and it was fine for another 500 miles or so, and now 4 cylinders have same codes, so any ideas what could cause this, I checked for shorts in wire harness injectors from DME, no change.

[ahlem]

Also check your compression across all cylinders. I had engine misfire codes and the cause was a bad head gasket.