1349, 1351 misfires and loud rattle on acceleration

[Danger]

Hello folks. Really need help here. Have been getting p1349, p1351 codes when slowing down to a stop or at idle. Also, getting a loud rattle (with and without CEL) when accelerating and pressing on the throttle. I have switched coils and plugs around but the same codes pop up for the same two cylinders with the occasional p0300. I know that it might be the injectors at this point, but it all started after an oil change in which I believe I put too much oil by accident (maybe by a half quart or so). I checked the plugs and they were a bit dirty with oil. The holes themselves (onto which the plugs seal) are extremely dirty with fluorocarbons. Have also tried new gas, cleaned the DISA and ICV with same results. The plugs only have less than 10,000 miles in them.

As for the rattle, it only happens when moving and accelerating; not when revving it up parked. I'm not sure that it is the VANOS as I wouldn't think that would ultimately trigger a misfire code. I'm really at a loss for options at this point.

I had similar issues about 5 months ago and it turned out to be a bad plug, bit there was no rattling sound at all.

I have searched the site extensively but can't find anything definitive. Any help would really be welcomed at this point.

[Nik]

Does error only show up after Idle?

[Danger]

Yes, if I stay at a stop light long enough the light goes on and car shakes a bit. Occasionally the light will come on while decelerating.

[Danger]

P1351 Misfire cylinder 5 with fuel cut-off is kicking my ass! Latest is I have tried/noticed the following:

-moved coils and plugs; misfire stayed with cylinder 5
-i get a sharp rattle when accelerating above 2000 rpms
-when CEL comes on the rattle stops but car drags and runs rough
-check codes and 9 out of 10 times it is P1351, occasionally p1349 and p0300 as well
-i clear the codes and same cycle starts as above

now, the loud rattle dying off with CEL would seem to indicate that it is ignition related - once the computer shuts of that cylinder due to misfire, the car runs rough on 5 cylinders but rattle is gone. but what is causing the rattling? it seems to come from the rear of the engine, right where cylinders 5 & 4 would be.

thinking it was a vacuum leak from the intake breather hose, i replaced it and found some creamy caramel gook, pointing to perhaps oil separator issues - which make sense given i had it replaced a few months back but have been suspect since. however, would a bad separator cause the misfires and rattle? i don't believe it's vanos cause it's not coming from the front of the engine and it dies off when the CEL comes on.

any insight? please? really need to get this fixed as i depend on this car quite a bit...

thanks in advance!

[Nik]

ok, After CEL smooth running is due to Fuel cut off on that cylinder. Could be said that it pulls less after that?(drivers slower?) try Discconecting MAF(mass air sensor) and see Idle, just to be sure that It's not MAF. It's a tricky thing, that MAF. Does it have alot of smoke at the exhaust? That reffers to PCV valve. start with that) hard to say, I am not that into it also. Hoping that ur car never ran into a river or so.

[Wayne's World]

Danger - if you want to go down the MAF route, i'm currently selling one right now. Not sure where in NJ you are but I've got it up on ebay. VDO Mass Air Flow Sensor (MAF) BMW Part# 13627567451 - eBay (item 170618242110 end time Mar-27-11 11:44:21 PDT)

It's a new VDO MAF for my 3.0.

[Danger]

UPDATE - EXPERT INSIGHT DESPERATELY NEEDED

Frustrated beyond belief, I took the car to the mechanic who replaced my CCV 5 months ago. His diagnosis is that it's a cylinder head issue - definitely the seal being compromised and the head potentially cracked. Cylinder 5 is leaking into 4 and compression test show seriously low compression particularly in cylinders 5 and 4. His guess is that moisture - possibly coolant- got to the oil. He estimated the bill at $3k, if I choose to fix it, or obviously more if I replace the engine.

Now, I have some major issues as to how this came to be, which of course he does not agree with, but is the reason why I brought it back to him in the first place. My case goes back to his replacing the oil separator. I never felt it was done right, given that (after the replacement) i would occasionally find that cream gunk at the dipstick and the oil cap, some hesitation when starting in cold weather, and no suction or pressure when releasing the oil cap when idle. About 2 months ago, I noticed some coolant loss, but the car has always had this issue, sometimes worse than others. Then two weeks ago I got the misfires (codes 1351, 1349, 1346, p0300, p0171) I documented in the original post along with consistent rough idle, and a loud tapping/ticking when accelerating and loss of power. At this time, I did some "clean up" along with replacing of the intake vacuum breather hose. Now when I did this, the connectors were full of the creamy gunk, indicating moisture. However, the car had not overheated during this period, was not burning white smoke out the pipes, and had not generated other codes (different than the above) that would indicate an issue with the cylinder head. Am I wrong with my suspicion of the CCV? When I bring this up to him, he says there is no way the CCV could generate those misfires (whether directly or indirectly via vacuum leak).

Sorry about the long post, but this is a major decision for me - whether to dish out $3k (a stretch for me) to fix this car (which i unfortunately depend on), or whether to ditch it given that if he is wrong and the issue persists, I simply would not be able to afford it.

Please, any insight to help in this decision is desperately sought.