N52 Burning Oil due to Bad PCV Diaphragm?

bshambam · 09-27-2020, 08:38 PM

Hey all,

I just replaced my valve cover gasket, Valvetronic Motor Gasket, and Eccentric Shaft Sensor Gasket. In addition to that, I replaced the PCV Hose, and Vacuum a booster hose.

The car is producing a bit of white smoke out of the tailpipe.
I suspect that a bad PCV Diaphragm is causing the engine to burn oil?

Can someone bounce off my thoughts?

I think I might need a new Valve Cover.

Thanks,

btw.

i'm not getting any engine codes.

4foothill · 09-28-2020, 06:34 AM

White smoke indicates coolant. How does the exhaust smell? Have you checked/done your oil filter housing gasket?

Do you have a whistling noise? Unstable idle? Does covering the hole on the PCV cap change the noise/fix the idle? You could probably test the PCV by unplugging the hose (so that the crankcase vents to atmosphere) and then bunging the hose.

wayman519 · 09-28-2020, 07:28 AM

Post your engine code and year of the car.

There are 2 types of PCV systems on the N52 engine.

E92William · 09-28-2020, 02:12 PM

Was it doing it before? You should record what the smoke looks like for everyone here to see. It's not uncommon that disturbing a valve cover that was leaking causes it to crap out, often cracking but could be this too.

Cruiser124 · 09-29-2020, 07:23 AM

I had a similar issue. Replaced all the same gaskets and upon reassembly the car was idling poorly and developed a whistle at idle and strong vacuum under oil cap.

First check to make sure your gasket didn't fold over when you installed it. In my case the cover was bad although the car had no symptoms prior just an oil leak so odd coincidence. I purchased a new Mostplus cover off Amazon for $100. Had good reviews and problem solved.

If you decide to replace the cover you can pop off the PCV cap on the back of your current cover and see if the diaphragm is torn. Only do this if you are replacing it as it's not meant to come apart

bshambam · 09-30-2020, 01:56 AM

odd thing is that i did a cold start and i wasn't getting smoke.
it seems to only smoke when it is warm....

i'm going to change the oil filter housing gasket and see if that does anything.

bshambam · 10-05-2020, 12:36 PM

I did the 'lift up the oil cap' test and it lifted up fine during idle.

The car is jacked up atm so I'm going to drain the oil & fluid, and then replace the oil filter housing gasket.

There was zero leaks from the outside of the housing unit.

09-27-2020, 08:38 PM	#1
bshambam Second Lieutenant 196 Rep 262 Posts Drives: bmw e91 Join Date: Jul 2020 Location: canada iTrader: (0)	N52 Burning Oil due to Bad PCV Diaphragm? Hey all, I just replaced my valve cover gasket, Valvetronic Motor Gasket, and Eccentric Shaft Sensor Gasket. In addition to that, I replaced the PCV Hose, and Vacuum a booster hose. The car is producing a bit of white smoke out of the tailpipe. I suspect that a bad PCV Diaphragm is causing the engine to burn oil? Can someone bounce off my thoughts? I think I might need a new Valve Cover. Thanks, btw. i'm not getting any engine codes. Last edited by bshambam; 09-27-2020 at 08:43 PM.. Reason: addition comments.
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09-28-2020, 06:34 AM	#2
4foothill Private First Class 31 Rep 131 Posts Drives: E90 325i LCI Join Date: Jun 2016 Location: Manchester iTrader: (0)	White smoke indicates coolant. How does the exhaust smell? Have you checked/done your oil filter housing gasket? Do you have a whistling noise? Unstable idle? Does covering the hole on the PCV cap change the noise/fix the idle? You could probably test the PCV by unplugging the hose (so that the crankcase vents to atmosphere) and then bunging the hose.
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09-28-2020, 07:28 AM	#3
wayman519 Second Lieutenant 79 Rep 250 Posts Drives: E82 N52 6MT A51 Join Date: Apr 2012 Location: Canada iTrader: (0) Garage List 2018 BMW X2 [0.00] 2009 128i [0.00]	Post your engine code and year of the car. There are 2 types of PCV systems on the N52 engine.
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09-28-2020, 02:12 PM	#4
E92William Banned 1998 Rep 2,026 Posts Drives: 2008 E92 328xi Join Date: Nov 2019 Location: Miami iTrader: (0) Garage List 2008 BMW 328xi [0.00]	Was it doing it before? You should record what the smoke looks like for everyone here to see. It's not uncommon that disturbing a valve cover that was leaking causes it to crap out, often cracking but could be this too.
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09-29-2020, 07:23 AM	#5
Cruiser124 Second Lieutenant 119 Rep 228 Posts Drives: 2006 BMW 330xi 6MT Join Date: Mar 2017 Location: Wisconsin iTrader: (0)	I had a similar issue. Replaced all the same gaskets and upon reassembly the car was idling poorly and developed a whistle at idle and strong vacuum under oil cap. First check to make sure your gasket didn't fold over when you installed it. In my case the cover was bad although the car had no symptoms prior just an oil leak so odd coincidence. I purchased a new Mostplus cover off Amazon for $100. Had good reviews and problem solved. If you decide to replace the cover you can pop off the PCV cap on the back of your current cover and see if the diaphragm is torn. Only do this if you are replacing it as it's not meant to come apart
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09-30-2020, 01:56 AM	#6
bshambam Second Lieutenant 196 Rep 262 Posts Drives: bmw e91 Join Date: Jul 2020 Location: canada iTrader: (0)	odd thing is that i did a cold start and i wasn't getting smoke. it seems to only smoke when it is warm.... i'm going to change the oil filter housing gasket and see if that does anything.
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10-05-2020, 12:36 PM	#7
bshambam Second Lieutenant 196 Rep 262 Posts Drives: bmw e91 Join Date: Jul 2020 Location: canada iTrader: (0)	I did the 'lift up the oil cap' test and it lifted up fine during idle. The car is jacked up atm so I'm going to drain the oil & fluid, and then replace the oil filter housing gasket. There was zero leaks from the outside of the housing unit.
	Appreciate 0 Quote