[splitsecond]

We just changed the valve cover gasket in my friend's 335i. Everything seemed to go alright overall, and the gasket seems to be in place, with no obvious leaks when I run a paper towel along the edges of the gasket.

After we changed it, it was a bit rough on idle initially, but that went away after it warmed up (might be because fuel lines were empty for a few seconds, might be because it's freezing outside and car hadn't been started for 3 days while we were occasionally putting off the project by an extra day because we needed more tools and it was already too late to buy them).

Anyway - we drove it around the block for a couple of minutes and came back. When looking under the hood, everything seemed fine, although we could smell some oil. Then suddenly, with the engine off, a cloud of white smoke started streaming out from underneath the engine on the passenger's side toward the rear end of the engine. I blew on it really hard and it just went away. A couple of minutes later, it came back and went away again after several seconds. This happened a total of 4 times, and then stopped. When we open the oil cap, there's no smoke underneath the valve cover.

I'm hoping it's just some extra oil that dripped into the bottom of the engine bay while we were working on the project. I can't think of any other explanation, since the smoke is coming from the bottom of the engine bay, well below anything we actually touched while working. Looking around the Internet, some people have had similar problems in the past both with bimmers and with other cars.

But the question is - could it be anything more serious? Is there anything in particular we should check before driving it?

[iDriveanXi]

Smoke is probably from oil on the exhaust and burning off. As for the idle hopefully it was just because it was cold. About an inch long section of my gasket came out of the groove and twisted which created a vacuum leak. It sealed the oil but air leaked causing crappy idle. I also had an SES light though.

[splitsecond]

So the smoke is improving now - guess that most of it burned off.

We're also noticing a bit of shakiness in the car as we try to drive it - feels like it's rocking a bit while we drive it. There's also an SES light. Feel a lot like my car did when I had a misfiring plug. I don't have a code reader because my car has a JB4, but his car doesn't, so I'm wondering if we have to suck it up and buy one to see if there's a misfire.

Is there a particular reason why we might get a misfire after doing the valve cover gasket? Maybe we broke a line without realizing it? We also changed the spark plugs, but they were well-seated, the coils were pushed down well, and the electrical sockets plugging into the coils were snug.

[splitsecond]

Turns out it's misfiring in multiple cylinders. Tried moving the coils around, and the misfire doesn't move with them. Any suggestions?

[kfrazie1]

What year is the car? How many miles ? Tuned or not? Original owner? Did you put in the original Bosch plugs? I would start looking into injector issues if you already checked the coils. Try to see if you can read the number on the side of the injector to see what version you have. Are you misfiring under only load, only at idle, or both. I've landed up replacing 2 injectors on my 335i in the past 3 months. I have an older recalled version. Have you ever had your HPFP replaced? Call BMW NA, give them your VIN, and find out if you have any outstanding recalls on the car. I actually replaced my VCG too a while back and didn't have any issues - actually fixed my oil burning issues.

[splitsecond]

2007, 106k miles, no tune, not original owner, yes used original Boch plugs. Misfiring at both idle and under load, but it seems much worse at idle.

We'll check into recalls, but it seems weird that 4 fuel injectors would suddenly die simultaneously right after doing a seemingly unrelated maintenance job... or am I missing something?

[iDriveanXi]

Did you disconnect the negative battery terminal before you began the repair? If not perhaps that may have tripped something up?

[splitsecond]

Yes we did

[still in school]

you're making me nervous about doing this on my own now.

[iDriveanXi]

Originally Posted by still in school

you're making me nervous about doing this on my own now.

It's not that bad. The cover itself is a pain to get out and back in. I'd recommend a helper with that part to hold stuff up and give you room. Follow pelican parts DIY or one on here and you'll be fine. Although things do happen but don't let it hold you back.

[BMW328icoupe]

Splitsecond - I have the exact same problem.

My car is a 2007 328i coupe with 130,000 km. I have done all maintenance myself since buying the car CPO from BMW with 47km. Anyway, I recently decided to change my VCG after seeing some oil residue on the exhaust side of the engine as preventative maintenance and the whole job seemed to go alright with no complications. I didn't take the plugs out bc that work had been done at 100,000 km . After reinstalling everything and letting the valvetronic motor automatically adjust, I started my car and it was immediately rough idle (pretty normal after major surgery I thought). It would idle up and down around 900-500. I got a CEL with P1415. I read a bunch of e90post forums (big thank you to everyone from a new user) that suggested to check for cracks in air filter housing tubes (vacuum leaks), coolant levels, and mass air flow etc. I bought mass air flow cleaner and used it, no cracks from any tubing on the air filter system, I decided to flush the coolant bc it was due anyway (using bmw coolant) but the problem still persisted. I used a bottle of concentrated engine cleaner ('guaranteed to pass' was recommended from a friend bc of how strong it is) to make sure no carbon was clogging anything up or was dislodged while VC was off or something. Problem still persisted. My symptoms include: 1) little bit of white smoke from left rear (passenger side when facing the engine) 2) engine still not idling properly 3)engine oil temp gauge at operating temp seems low. Even once completed warmed up and driven on the highway only settles at 100 C (Instead of centre of gauge like before 110 - 120C. I am in Toronto and it recently has been -10 out so that may be the reason 4) Oil smell periodically while stopped at a red light and car idling. 5) Oil level seems to be down a little 6)little bit of white smoke out of exhaust (probably due to engine detergent).

I decide to take the car into BMW to get a diagnosis and they said MAF needed to be replaced. The code their system read was "002D06 - DME: Mass Air Flow System" Technician said Air mass flow rate should be between 8.79kg/h - 13.19kg/h and mine was measured at 4.38kg/h (way too low and out of the required parameters.) I thought this was odd bc prior to the VCG I didn't have any CEL or problem with MAF which probably means the cleaner fried it. I bought a new MAF as recommended and installed it and still oil smell in cabin and rough idle. Im taking it back to BMW for them to re diagnose next wednesday and will let you guys know what they say. My guess is I very slightly over torqued the VCG bolts (even though i used a torque wrench and was careful or somehow the gasket wasn't seated correctly even though i ran my finger around the outside and felt it all the way around or the VC itself needs to be replaced bc of the oil separator is broken. Note: I only changed VCG, eccentric gasket, and valvetronic motor gasket and not the whole cover even though its plastic and is recommend. I was trying to save a few bucks bc the cover seemed in good shape (no oil pooling in spark plug holes etc)

Sorry for the long post, just wanted to be thorough.

Appreciate the advice in the meantime and will touch base once BMW tech looks at it again.

John

[splitsecond]

Thanks, my friend just took his car to a BMW tech too, so we'll see what that reveals...

We didn't get a P1415 code though... only misfire codes.

[BMW328icoupe]

So I brought my car into BMW this morning to get diagnostics done. For $166 they couldn't find anything wrong... bc I've done most of the service myself they don't have much history on the car and basically said they would need to charge approx $1000 to do smoke test and check valve timing/relearn valvetronic motor etc. They would need to take the VC off and check things out for themselves. The tech I had was actually a good guy although he wasn't crazy about me ordering a MAF from esctuning and installing it myself. (same part number as required but was suspicious if it worked properly or not bc it was made by continental vc siemens)...what do you guys think? BTW my car is completely stock with the exception of bilstein sport shocks and m3 control arms.... always buy all fluids from BMW, oil changed every 5,000km.

After reading the Bentley manual (purchased with MAF after VCG order from Ecs), I think I've narrowed down the problem to a couple things.

1) When I did the VCG job, I'm quite certain the main gasket itself is seated correctly. When I did the research leading up to the job, most of the forums i read said to just unscrew the 3 Valvetronic motor screws and it springs out. They also said to make sure to reengage the gears on the way in, which i did. But I didn't turn the small allen key on the Valvetronic counterclockwise and then clockwise as Bentley has stated which has me thinking the valves aren't completely shutting/opening when they are suppose to causing the car to burn oil when hard on the throttle occasionally.

2) The VC itself is broken/cracked causing either a micro vacuum leak or the oil separator function isn't working properly. (Oil cap comes off without any suction when engine is running so I don't think its vacuum) I don't see any oil whatsoever leaking or pooling anywhere on the cover or beside the engine but prior to the job the car was working fine (except for oil residue on left side of engine which is why i did the VCG in the first place) so this tells me I did something incorrectly during the change. Also, the BMW tech said that the valvetronic needs to be relearned via his computer not on its own but I've read on here that the system relearns its limits on its own when you put the key in for 10 seconds in second position (not started).

3) The cars computer is just confused and needs to be master reset or updated. I had one of the red battery cables unplugged during the whole job so I guess it should be fine but something is obviously not right.

Appreciate the advice. Cheers

John

[Cbozz]

Originally Posted by splitsecond

2007, 106k miles, no tune, not original owner, yes used original Boch plugs. Misfiring at both idle and under load, but it seems much worse at idle.

We'll check into recalls, but it seems weird that 4 fuel injectors would suddenly die simultaneously right after doing a seemingly unrelated maintenance job... or am I missing something?

did you torque all bolts up to specs?

[BMW328icoupe]

Any thoughts gentlemen?

[knux11]

you ever figure this out?

[ewrjontan]

I know this is old but my car is experiencing similar issues after my ccv install. Misfires and maf codes. Found my valvetronic motor gasket is leaking but I don’t think that would cause misfires or the exhaust smoke I’m getting on acceleration.