SOLVED - Engine Failsafe after Valve Cover Seal Replacement for Blue Smoke

[McDonaldD]

I would not recommend disconnecting the PRV lines while the engine is running. You'd likely not do any damage, but its not worth the risk. Even if you managed to seal the intake ports, its not worth the risk of one of those fashioned-seals failing and being sucked into your engine...in such a case, you'd almost certainly need to rebuild your engine.

But, if you insist on doing so, you'd need to fashion some kind of air tight (vacuum tight) seal/cap for open ports on the intake manifold - where the PRV's hoses were disconnected - doing so would prevent oil from being drawn into the intake manifold but would not stop oil from splashing out of the valve cover via the PRVs. You would need plug these as well. However, the valve covers (and crankcase, in general) are not designed to be under pressure; which would be generated by blow-by gas during normal operation. Since there already seems to be a leak in the crankcase, you might get away with simply plugging the PRV's port because the leak may be large enough that it would prevent pressure from building, much in the same way it prevented a vacuum from forming...but you'd be gambling on this. I do not know the extent of damage that could be done if the crankcase were to become pressurized: it could be no damage, it could be negligible "damage" like a little more oil gets pushed out, or it could cause oil to be forced past piston rings and into your combustion chamber...

I have not fully reasoned through the implications of sealing off the PRV, even for testing. It certainly cannot be "good" for any of the crankcase seals...assuming it is sealed enough to build a pervasive pressure in the absence of a strong vacuum to evacuate such a pressure.

Also, I do not see what you would gain from disconnecting the PRVs.


With the engine off, you can check if oil is being drawn into the intake by:

1., disconnecting the plastic intake duct, attached to the throttle body,
2., pushing open the throttle plate,
3., and looking inside using a flashlight.

If the interior of the intake is even remotely wet and/or coated in oil, its coming from at least one of the PRVs; being the only possible source of oil in the intake, at least on the e53's N62. A similar test can be done by disconnecting the PRV's tube at the intake and checking for oil stains in the, now, open port.

[BenSF]

McDonaldD - Amazing write-up! Very happy to find someone with the exact problem and it appears that you fixed the issue! Congrats and thank you for taking the time to share your experience with us. Very encouraging that it could something other than a blown head gasket that will cost us thousands to fix! I was recently laid off and can't afford a $8K fix, so your post is a relief and gives me hope. I love my X5 and but for the "cloud of shame" the car runs like a champ!

My white smoke issue started about a month ago - my 2006 X5 4.4L (E53/N62) with 80,000 miles - "an embarrassing cloud of shame - typically after accelerating from prolonged idling." Happens more noticeably on warm sunny days. Only difference is the smoke is only coming out of the driver's side tailpipe.

I replaced my Pressure Regulating Valves, as many suggested, but that didn't help since they weren't torn.

McDonaldD - I am a DIYer that is somewhat mechanically inclined and recently completed simple stuff like changing my brake pads and rotors, oil/filter changes, etc. But what you are describing seems a little over my head. So I would like to ask for a favor and propose to ask for your help. It appears that we live close by, I am in San Francisco. I propose that I will buy all the parts and over a day or two get your help with doing exactly what you did on your X5 and I could compensate you for your time. It would be a great learning experience for me as well. That would be a tremendous help to me, let me know if you are willing and have the time.

BenSF

[McDonaldD]

pcb5 - Everything is running great! I recently changed the fluid/filters in my transmission and differentials - After all of the work, I'm now averaging a combined 19.7 Smoke-FreeMPG - compared to ~16 SmokeFullMPG. Aside from replacing a flatted/slashed tire from my last trip to Tahoe, my next task is to track down a permanent fix for the random yellow tinge that my Nav screen has become increasingly fond of.

BenSF - The post-fastrak stop light on Bay Bridge helped render some of my car's finest works. If you can wait about two weeks, I can free up the time to work with you. Its quite the job but nothing to be afraid of: 1 full day would be cutting it close, a plan calling for two would be wise. Do you have a garage, an arsenal of tools, jack, jack-stands, and a desire to feel insanely accomplished? As long as you have the last one, I'm happy to help; everything else can be worked out.

The wait is perfect for you to order parts - While helpful and convenient, BMW of SF can get quite pricey. I believe I still have my parts list(s)/receipts(prices) from when I did it...but its probably best to hash those details out through e-mail, phone, or otherwise. Let me know, I'll be back in the city by Tuesday, July 9th, but I'll be pretty busy through the 17th or 18th. My e-mail is just my username at either me.com or berkeley.edu - I haven't had a lot of luck being notified of private messages on here.

[BigBlack48is]

Originally Posted by McDonaldD

pcb5 - Everything is running great! I recently changed the fluid/filters in my transmission and differentials - After all of the work, I'm now averaging a combined 19.7 Smoke-FreeMPG - compared to ~16 SmokeFullMPG. Aside from replacing a flatted/slashed tire from my last trip to Tahoe, my next task is to track down a permanent fix for the random yellow tinge that my Nav screen has become increasingly fond of.

BenSF - The post-fastrak stop light on Bay Bridge helped render some of my car's finest works. If you can wait about two weeks, I can free up the time to work with you. Its quite the job but nothing to be afraid of: 1 full day would be cutting it close, a plan calling for two would be wise. Do you have a garage, an arsenal of tools, jack, jack-stands, and a desire to feel insanely accomplished? As long as you have the last one, I'm happy to help; everything else can be worked out.

The wait is perfect for you to order parts - While helpful and convenient, BMW of SF can get quite pricey. I believe I still have my parts list(s)/receipts(prices) from when I did it...but its probably best to hash those details out through e-mail, phone, or otherwise. Let me know, I'll be back in the city by Tuesday, July 9th, but I'll be pretty busy through the 17th or 18th. My e-mail is just my username at either me.com or berkeley.edu - I haven't had a lot of luck being notified of private messages on here.

What a guy!! I wish I lived on the west coast