[BRNX_E90]

Hi,

I am a relatively new person to the Forum.
I do alot of reading here, but do not post that much.
But, I do have a question...and require some help.

I have a 2007 BMW 328 Xi - 112,000 Miles
Currently the Car has the SES light on - scanning it with a generic scanner - i get the code P0306 - Cylinder 6 Misfire.

This started last week, after purchasing some gas - Im not sure if this may be a cause or not, or if it relates to the issue but here goes.

Ive noticed that when I start the car, a sort of smell comes from it - smells like gas/oil - lasts about a minute and then clears up.

The real problem I notice, happens when im at a stop light or stop sign.
When driving the car, i notice nothing really different. however, if i come to a stop sign or stop light, the car idles usually at 600 RPM - but every 10 seconds or so it seems to "miss" or "jump" up in RPM to about 750 for a second and then return back to idling at 600.

Example, So say at a stop light for 1 minute - the car will have this episode for maybe 5 or 6 times. However, I did notice - if i place the car in neutral ... the car doesnt do it - or maybe hasnt done it yet. This has been happening for about 3 days now.

I am thinking that P0306 - with the cylinder 6 misfire - could be a spark plug/ ignition coil - could someone point me in the right direction? - which coil should I buy - is bosch fine? or should it be BMW.

I spoke to a "car guy" and he told me, that theres a possibility that it may be related to "bad gas".

Im truly sorry that this post is so long...I do really appreciate any and all help.

Thank You,

[The Nightman]

Easiest way to diagnose a faulty ignition coil is to swap it with another cylinder and see if the error code follows it. What you're describing does sound like an ignition coil though. I'd also replace your spark plugs if they're still the original.

I believe Delphi coils superseded Bosche but check on realoem.

[BRNX_E90]

Thank You so very much for your response!

Would you think that the slight scent that I get is relating to the coils as well??

[STR8-6IX]

Originally Posted by BRNX_E90

Thank You so very much for your response!

Would you think that the slight scent that I get is relating to the coils as well??

the smell should not be related to coils.

I would swap an ignition coil with cylinder 6 and check to see if the misfire is moved to a different cylinder.

I just replaced cylinder 4 ignition coil yesterday at 75k.. would have lasted much longer if I changed spark plugs at 60k. worn spark plugs wear out ignition coils very quickly