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Discussion Starter #1 (Edited)
Ok so im driving home last night, bout an hour drive. The car is running great, pulling hard and smooth as usual. Now this morning i go to start it up and it idles pretty rough for the first few seconds, then it smooths out. I didnt really think anything of it. Drive it to Best Buy its all good. Go to start it up when i leave, and the check engine light pops on and the car runs terribly. Runs rough like its misfiring and has ZERO power. And the exhaust sounds different...kind of louder and blattier... Like the timing is completly off. Went to autozone to get it scanned and it had 12 codes in it. the generic codes were PO340, PO012, PO141, PO305, 306, 307 308, and 300....and there were duplicate codes of a few of them. Basically its throwing what looks like(to me) an Intake bank one cam sensor code, Valve timing bank one over-retard, o2 sensor,evap emission,and a cylinder 5,6,7,8 misfire code along with a random multiple miss code(300). So.....where do i start with this? Does this sound electronic or mechanical? It does have a slight rattle on start up, and ive got a new timing chain tensioner on order form ecs tuning, do you think it could of jumped a tooth? its only got 79k on it....
Or does this sound like a cam sensor or vanos issue? Car has run fine up until this point and there were no other historic codes....
:grrrrr::Thumbdown::crying2:
 

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Likely, it is the Bank1 (the side in which the oil goes) Inlet CPS and possible bank1 post-cat' O2. Clear the fault codes and see what comes back. The Post-Cat O2, I would not worry about until after the timing codes are resolved. I had the same O2 fault once. I have not yet replaced the O2 as it has not come back in over two years.
 

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Discussion Starter #3
Ok, had the codes cleared and drove it home. Still doesnt feel quite right, but at least it stopped missing. light dodnt come on yet but only one key cycle. probably wont drive it again until tommorow. Ive ordered a cam sensor, looks like the updated one that doesnt have the taper. Hopefully this should fix the problem. In the meantime, is the car safe to drive? I imagine it wont be good for the plugs or the cats...but can it cause any physical damage? rapid carbon buildup perhaps?
 

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I wouldn't drive mine, but I have a couple of alternates. It may not perform as expected but one the fault returns, it will go into failsafe (Limp Mode). Typically, it will take at least two consecutive drive cycles with a recurrent code, or for the code to present twice for a long enough period to set the MIL.

When you do the CPS, you might want to seriously consider replacing the SHCS (Socket Head Cap Screw (Allen Bolt)) retaining the CPS. The SHCS is a PITA to remove as you will need to remove the bracket to access the bolt. A HHCS (Hex Head Cap Screw) may make the job much easier when next it fails. Also, you should be able to put the bracket back in place with the CPS on acting as a huge obstruction.
 

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Discussion Starter #5
I can drive my GFs car around if i need too. So youre saying to replace the bolt that holds the CPS in with a regular bold vice the allen head style that came stock?
 

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Yes. I would recommend either a zinc oxide plated or stainless steel (m6x25). Ideally the new fastener will also have a captured washer but a small flat washer (SS) will work as well.
 

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Discussion Starter #7
Ok thanks ill remember that. Hope all it needs is a Cam sensor. Vanos board mnt. is planned for this winter...was hoping to hold off a few months for it. gotta order the seals.
 

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Discussion Starter #9 (Edited)
Edit: so the driver side (bank 2) is cylinder 5 thru 8. Passenger side (bank one) is cylinder 1 thru 4. The code is P0340.. cps intake bank one. So why is 5 thru 8 misfiring? Are the bank numbers different for usdm versus eudm? I'm confused
 

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Like I said, weird.
It was definitely the bank 1 (passenger side) intake cam CPS that was acting up, and it was the bank 2 (driver's side) cylinders that were misfiring. But they could have been stored codes for separate problems.
Keep driving it and wait to see what comes back.
 
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