BMW E90 misfiring

[ZSP-Mafia]

I asked this over on bfc but figured Id ask here as well since I know a few guys here own e90's. My friends 06 325 has been running rough and just threw a code "P0314 Single Cylinder Misfire (Cylinder not Specified)" which is a Generic non BMW code. He also just informed me that his wife recentlygot the oil changed at Jiffy Lube :rolleyes and she didn't want to pay extra for synthetic. I advised him to change the oil immediately, but do you think that the oil could be the cause of the problem?

[Marcus-SanDiego]

I asked this over on bfc but figured Id ask here as well since I know a few guys here own e90's. My friends 06 325 has been running rough and just threw a code "P0314 Single Cylinder Misfire (Cylinder not Specified)" which is a Generic non BMW code. He also just informed me that his wife recentlygot the oil changed at Jiffy Lube :rolleyes and she didn't want to pay extra for synthetic. I advised him to change the oil immediately, but do you think that the oil could be the cause of the problem?

Not going to comment on the oil, but another thing to change is oil filter. Jiffy Lube is notorious for putting in filters that degrade terribly.

[kayger12]

I'm thinking if the highly trained engine lubricant replacement technician at Jiffy Lube put in the wrong viscosity oil there could be an issue. From a Porsche board:

There are manufacturer bulletins about "no starts" and "misfires" if the incorrect oil viscosity is used, especially when the weather turns cold. On some vehicles, when using the incorrect viscosity oil, the hydraulic valve lifters will not bleed down quick enough, leaving the valves open and causing a no start or an engine misfire. With your Porsche, oil viscosity and quality are so important because of the hydraulic lifters, the variable cam timing, and the variable valve lift; all which operate off of oil pressure and oil flow.

[ZSP-Mafia]

He's taking it to an Indy right now.

[danewilson77]

Oil prolly not the cause.

How is the car running?

[ZSP-Mafia]

He said it feels like it's misfiring.

[danewilson77]

Could be plugs, coil, big intake leak, failed MAF sensor. Idk....if it has anything to do with oil change.

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[Maximus57]

I had to replace the MAFS in my current car. It wasn't misfiring due to the failed MAFS.

[danewilson77]

I had to replace the MAFS in my current car. It wasn't misfiring due to the failed MAFS.

Wut?

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[az3579]

Wut?

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Mass Air Flow Sensor.

[danewilson77]

No kidding. He says he had to replace maf sensor in current but it wasn't misfiring due to bad maf sensor. I just didn't understand the reference.

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[az3579]

I don't understand the correlation either, to be honest. Perhaps the air/fuel mixture wasn't correct for spark? Remote possibility though I don't think so.
I wouldn't think the oil viscosity would have anything to do with it, but then again, I'm not a mechanic so I wouldn't know. Was a tune-up done recently? How many miles on the engine?
Perhaps one of the plugs is fouled up too much at this point.

[ZSP-Mafia]

I'm waiting to hear what the Indy had to say. The car has never had a tuneup IIRC, it's only got 38,000 miles on it.

[az3579]

I'm waiting to hear what the Indy had to say. The car has never had a tuneup IIRC, it's only got 38,000 miles on it.

Well if the car is used in mainly stop&go, I wouldn't be surprised if it needed a tuneup soon.

[danewilson77]

Well if the car is used in mainly stop&go, I wouldn't be surprised if it needed a tuneup soon.

Define tune up pls.

[Maximus57]

No kidding. He says he had to replace maf sensor in current but it wasn't misfiring due to bad maf sensor. I just didn't understand the reference.

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The reference was from you Dane, You stated this E90 could be misfiring due to plugs or MAF. I stated my current car had a failed MAFS and it wasn't misfiring. Therefore it's doubtful this E90 was misfiring due to a bad MAFS.

[danewilson77]

ok...He took it to indy right?

[ZSP-Mafia]

ok...He took it to indy right?

Yah, haven't heard back from him yet though.

[gr330zhp]

Thats low mileage for an E90 325i. The car probably just needs to be driven. I say change oil, fill up with a good tank of 93 and drive it hard for a bit. Too young to have issues in my opinion....