[maximoline]

Hey guys, so ive been dealing with this slight rough idle for quite some time now and I cant seem to figure out what the problem is. It all started when i felt the car pulsate a little when i stopped at red lights and such. Was gonna get it checked out but ended up not having the time. Then, a couple weeks later i started the car and it started shaking profusely. i couldn't even drive it. turns out I was having misfires in cylinder 6. I ordered all new coils and Plugs hoping that was it(also i didn't know when they were last changed so wanted to change them anyways). when i took the ignition coil out i noticed there was oil in several of the spark plug wells(took all of it out with a spray bottle and a rag on a small Flathead). Then i ordered a valve cover gasket and all spark plug tube seals and replaced all of those. After the VCG change i turned the car on and the rough idle stopped but it shook a little for like a minute when i turned it on and i noticed the rpms were a little jumpy. My friend who knows much more about cars than i do told me it was nothing and should go away soon. so i continued to drive it until one day when I went to start the car and it wouldn't start. Ended up being a loose terminal but The SES light came on so i scanned it and noticed that i had the codes P0171 and P0174 bank 1 and 2 system too lean. Wasnt sure what it was but a couple days later i turned on the heater because it was cold and it smelled a little funky. so i turned it off and put the AC on full blast to get rid of the smell. then i noticed a little bit of smoke coming out of the hood and pulled over immediately(ended up being a loose cable burning some plastic. anyways it gave me an SES light and the code P00BC MAF "A" Circuit Range/Performance Flow Too Low. Now its been about two months and the car still shakes a little when i starts and sometimes at red lights. can anyone please help me figure out what this is? maybe a vacuum leak? or bad pcv? also included a video and a lot of greyish smoke come out of the exhaust.(watch till the end a lot more comes out)

2007 bmw e92 328i N52 pre facelift

pulled out some ignition coils yesterday to check and no oil.
also tested all the injectors yesterday and they seemed all good.

[Mgh024]

Try running a fuel system cleaner.

[E92William]

Hey brother. First thing I would try would be when it's doing that after its idling fine being warm you try and open the oil fill cap. Often when the pcv goes bad or gets stuck it can cause it to even stall. Mine got stuck closed and after a bit of driving the crankcase pressure would be so high it would cause the engine to stall it would also whistle a bit. Stuck open would very well indicate a lot of air going in the intake which I would hope isnt because then you're looking at a new valve cover with either of these two issues.
I would suggest a good injector cleaner but probably not a fix.
Go ahead and disconnect the maf sensor and run the car if it wont start without it disconnect it while running the engine. Often times it can just go bad. Swap coils from 6 to 5 and clear codes check for the misfire again.
That smoke could very well be just condensation on the bit colder weather

[E92William]

I think your symptoms do sound like a bad pcv. Mine would stumble at red lights and borderline stall out. You really should have changed that cover with a new one while you were there. Though I've seen people replace the pcv with the cover on the car. I'd look into that.
The cyclone oil separator can get clogged too

[maximoline]

Originally Posted by E92William

Hey brother. First thing I would try would be when it's doing that after its idling fine being warm you try and open the oil fill cap. Often when the pcv goes bad or gets stuck it can cause it to even stall. Mine got stuck closed and after a bit of driving the crankcase pressure would be so high it would cause the engine to stall it would also whistle a bit. Stuck open would very well indicate a lot of air going in the intake which I would hope isnt because then you're looking at a new valve cover with either of these two issues.
I would suggest a good injector cleaner but probably not a fix.
Go ahead and disconnect the maf sensor and run the car if it wont start without it disconnect it while running the engine. Often times it can just go bad. Swap coils from 6 to 5 and clear codes check for the misfire again.
That smoke could very well be just condensation on the bit colder weather

The misfire code went away about I month ago sorry I forgot to include that. Also I tried using an injector cleaner and it didn't seem to do anything really. I'll try the oil cap trick in a bit and get back to you. Is it supposed to change when I open it or stay the same?

[JonOhh]

There should be a slight vacuum when you attempt to open the oil cap, just enough to feel and hear sucking sound as soon as you break the seal. If there is no vacuum at all, or if there is a lot of vacuum causing you to have to pull very hard to get the cap to open, then you have an issue.


The general rule is that the car should continue to idle, although I believe a mild stutter or idle speed fluctuation is normal. I've found inconsistent behavior when doing this to mine, sometimes it idles unaffected, sometimes it fluctuates, and once it even stalled, but all seems to be fine, so your mileage may vary.

[andy8kahn]

I have the first problem with my 2007 BMW 328i Sedan. I get rough Idle when AC is off. I feel vibrations esp in my seat at stop lights. If AC button is on, then the vibrations are either not there or really mild.

I do have a leaky VCG but if that is the problem, why turning on AC resolves most vibrations? Any suggestion would be appreciated.

Note: My car has 100K miles and I just changed the Spark Plugs.. The problem was there before Spark Plug replacement and it did not resolve the issue...

[maximoline]

Originally Posted by JonOhh

There should be a slight vacuum when you attempt to open the oil cap, just enough to feel and hear sucking sound as soon as you break the seal. If there is no vacuum at all, or if there is a lot of vacuum causing you to have to pull very hard to get the cap to open, then you have an issue.


The general rule is that the car should continue to idle, although I believe a mild stutter or idle speed fluctuation is normal. I've found inconsistent behavior when doing this to mine, sometimes it idles unaffected, sometimes it fluctuates, and once it even stalled, but all seems to be fine, so your mileage may vary.

Here's the video of me pulling the cap off. I didn't feel any vacuum at all but I've pulled it off before it's warmed up and felt vacuum. So maybe it was so slight that I just couldn't tell. Also is it normal for my injectors to be that loud?

[C4maro]

Taking off VC could maybe create an issue with an already faulty pcv, if yours is original it would be good to replace anyway and sounds like your problem. Easy to replace with YouTube video.

[JonOhh]

Originally Posted by maximoline

Here's the video of me pulling the cap off. I didn't feel any vacuum at all but I've pulled it off before it's warmed up and felt vacuum. So maybe it was so slight that I just couldn't tell. Also is it normal for my injectors to be that loud?

Injectors sound fine, about the same as mine. Also, I heard a slight hiss when you broke the seal open, which is right.

I'd still check all hoses (especially the plastic ones) near the VC and Manifold. It's possible to have a slight leak and still have the CCV system work seemingly correctly (the test is hardly scientific).

[maximoline]

Could this also be that I planted the valve cover on wrong and pinched it causing a vacuum leak?

[maximoline]

Update: still haven't been able to fix it and I haven't been going out because of COVID-19. The other day I had to go get groceries and when I returned home a ton of smoke started coming out of the hood because oil was leaking out onto the headers. Would this help anyone identify my problem please?

[relative4]

Yeah, you probably pinched the gasket.

[clegg]

You for sure have a VCG leak and vacuum or PCV issue. The pcv valve is molded to the VC on this model BMW. Just replace the whole valve cover.

My daughters 08 328 had the smoking from oil leaking onto the exhaust manifold and I replaced the complete VC. I bought it complete, came with all gaskets, pcv, mounting bolts and all. It was $100. It's been on for 3 months now and all is good.

If you do replace the VC, be sure to properly reconnect all wiring and vac connections.

[maximoline]

Originally Posted by clegg

You for sure have a VCG leak and vacuum or PCV issue. The pcv valve is molded to the VC on this model BMW. Just replace the whole valve cover.

My daughters 08 328 had the smoking from oil leaking onto the exhaust manifold and I replaced the complete VC. I bought it complete, came with all gaskets, pcv, mounting bolts and all. It was $100. It's been on for 3 months now and all is good.

Where did you get the valve cover?

[mweisdorfer]

Run two full tanks with techtron 20 gallon formula with 93 octane, in a row.

Change out your PCV.

How many miles on this n52?

[maximoline]

Originally Posted by mweisdorfer

Run two full tanks with techtron 20 gallon formula with 93 octane, in a row.

Change out your PCV.

How many miles on this n52?

113,000 miles

[mweisdorfer]

Originally Posted by maximoline

113,000 miles

Your injectors May or May not be toast. Idk...

I don't like the oil found in the spark plug cylinder.

Transmission fluid & Filter Pan Changed?

[maximoline]

Turned the car on to go park in the garage and immediately started smoking. Looks like oil is leaking onto the headers. Could this maybe be a pinched gasket? And if it is should I just change the gasket again correctly or just get a new valve cover?[IMG][/IMG]

[E92William]

You for sure have a valve cover gasket leak. I was gonna buy an e92 and i started it up and the sucker was just pouring out of the gasket in the headers just like yours. Bite the bullet get a cover because mine had a pcv fail at about that mileage anyway, it doesnt have to be OEM look around and use a good gasket. Also scan for codes.

[maximoline]

Originally Posted by E92William

You for sure have a valve cover gasket leak. I was gonna buy an e92 and i started it up and the sucker was just pouring out of the gasket in the headers just like yours. Bite the bullet get a cover because mine had a pcv fail at about that mileage anyway, it doesnt have to be OEM look around and use a good gasket. Also scan for codes.

Just bought a a URO valve cover with a 2 year warranty off Ecs tuning! Hopefully it fixes the problem

[SabineBimmer]

Originally Posted by E92William

Hey brother. First thing I would try would be when it's doing that after its idling fine being warm you try and open the oil fill cap. Often when the pcv goes bad or gets stuck it can cause it to even stall. Mine got stuck closed and after a bit of driving the crankcase pressure would be so high it would cause the engine to stall it would also whistle a bit. Stuck open would very well indicate a lot of air going in the intake which I would hope isnt because then you're looking at a new valve cover with either of these two issues.
I would suggest a good injector cleaner but probably not a fix.
Go ahead and disconnect the maf sensor and run the car if it wont start without it disconnect it while running the engine. Often times it can just go bad. Swap coils from 6 to 5 and clear codes check for the misfire again.
That smoke could very well be just condensation on the bit colder weather

Pretty sure this is it. Good luck!