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Engine smoking issue

7K views 37 replies 20 participants last post by  Alwaysneedhelp 
#1 ·
Hello, I'm new to this forum...it appears that there are many members that know quite a bit about the cars we drive.

I own a 2006 750iL with 118,000. I took the car to get it smog checked and the car was runing great, no smoke or any other issues. When the smog technitian put the car on the dyno and reved up the engine to run the smog test and once he stoped the reving of the engine, I noticed a cloud of smoke that came out of the tail pipe.

Since then, I have noticed that the car will release a cloud of somoke every once in a while. It doesn't do it constantly, it happens every once in a while. Since this began happening, I have noticed that the car oil level drops and I have to add a quart of oil at least every 3 weeks.

I took the car to the dealer and they told me that the problem has to do with the "Engine Valves Guides". They said that these cars, once the mileage reaches 100K, that the engine heads need to be repaired.

My question is, has anyone out there experienced this type of problem with smoking and engine oil loss? Any idea what needs to be done? Is the dealer telling me the truth?

Please advise.

Thanks!
 
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#2 ·
It's a pretty common issue and it's well known here. There are these seals called the Valve Stem Seals and they end up going bad and you start burning oil and seeing the "puff of white smoke". Replacing them can be troublesome but a lot of independent places can do it as well.
 
#6 ·
The big thing is that these valve stem seals are going because of the EXTENDED 15K mile oil changes that people were doing in 2002-2005 with ****ty oil! The oil BMW uses got better over time to actually last that long without an issue!
 
#7 ·
I don't think there is any definitive answer for valve stem wear. There seems to be speculations that the cause is from extended oil changes etc.. which has yet to be proven. I beg to differ on that note. BMW just simply made a bad design of the N62 engine.
 
#8 ·
I own a 2006 750iL with 118,000. I took the car to get it smog checked and the car was runing great, no smoke or any other issues. When the smog technitian put the car on the dyno and reved up the engine to run the smog test and once he stoped the reving of the engine, I noticed a cloud of smoke that came out of the tail pipe.
So my question is, did you pass smog? If so, would you mind posting the readings? Just curious to see what the levels are with the smoke problem.
 
#9 · (Edited)
RE: White Smoke at idle

Hello, I'm new to this forum...it appears that there are many members that know quite a bit about the cars we drive.

I own a 2006 750iL with 118,000. I took the car to get it smog checked and the car was runing great, no smoke or any other issues. When the smog technitian put the car on the dyno and reved up the engine to run the smog test and once he stoped the reving of the engine, I noticed a cloud of smoke that came out of the tail pipe.

Since then, I have noticed that the car will release a cloud of somoke every once in a while. It doesn't do it constantly, it happens every once in a while. Since this began happening, I have noticed that the car oil level drops and I have to add a quart of oil at least every 3 weeks.

I took the car to the dealer and they told me that the problem has to do with the "Engine Valves Guides". They said that these cars, once the mileage reaches 100K, that the engine heads need to be repaired.

My question is, has anyone out there experienced this type of problem with smoking and engine oil loss? Any idea what needs to be done? Is the dealer telling me the truth?

Please advise.

Thanks!
Hello. I'm in Atlanta area, have a 2003 BMW 745Li with only 82k that I love, and owe on...haha. Experiencing the white smoke at idle issue, yes, I know, its the Valve Stem Seals passing oil thru the exhaust.
So...after conferring with my mechanic associates (I'm in the car biz) and reading these informative posts, I have found the 'Dirty Little secret #745' of the BMW shop manual.
As a good handfull of 7 Series owners have related, they're had the Valve Stem Seals replaced by BMW dealerships at anywhere from $4800. to $6500.. am I correct, posters?
I'm certain thats a thorough process...removing the entire engine, pulling the heads, all to replace these little Seal rings. Sounded too bad to be true. Especially in my case, as there are no other leaks or issues.
Well, there is another workaround, please correct or confirm if you're truly knowlegeable. An Indy or off-the-clock BMW tech can use compressed air (using a hose & fitting threaded for the spark plug hole) to bring up the valve stems so they're accessable, and they pull each one and replace, without removing the heads or the engine. See KeifR's Excellent Flickr Photo detail of the process...awesome pics. According to my sources, the replacement seals are superior to the Original ones, anyone know if that's a fact? I've seen the compressed air fitting, I have a former BMW Shop tech who confirms that this is the 'workaround', and he can perform it in 8-10 hours at his home shop, as opposed to 40-50 BMW Shop Labor Hours. we're talking less than $1000. as opposed to over $4500. I am going to let him do it and promise to post my results here for everyone to read. Feel free to correct or confirm, or tell the Forum that I dont know what the hell I am talking about, haha, I'm sure you all will! But, I've done my homework, and I must try it, don't have $5000. to invest in the issue, anyway. Good luck to all, feel free to message me for info. Thanks
 

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#11 ·
How many People have actually had the Valve Stem Seals Changed? I have seen 1 DYI on here, but I think it is a common job on this car? Maybe 20% of engines over 100K miles.

Here are the symptoms (I have it too)

No problem at start up.
After car has warmed up, it produces a big puff of smoke after idling for a few minutes.
(Mine just produces the smoke from the driver side exhaust only.... (Is this the common, or do people see it on both sides?))

Repairs I have done.
Lower Oil Pan gasket
Both valve covers with upper timing covers
Alternator gasket
Vacuum Pump
Crank Case Valves PCV, and new hoses
(I also tried to pour Seafoam into the crankcase PCV, did nothing)

$1000 for this repair job is a deal!!! Most shops dont even want to talk about the work around, anyone know where to get a loaner cam adjusting tool set?
 
#19 · (Edited)
I HAVE A 2002 BMW 745Li AND MY BMW STARTS SMOKING IF I LEAVE IT ON FOR LIKE THREE TO FIVE MINUTES OR SOMETIMES EVEN AT A STOP LIGHT, IS THERE ANYONE WHO CAN TELL ME WHERE CAN I GET THIS FIXED IN GLENDALE ARIZONA ?
If you do find one, please share! have an 04 with 116k with the same issue.

btw: To those that have had this issue or are having this issue, will driving the car continuously be a bad idea? will it cause any kind of damage to the motor or cause more issues?
 
#14 ·
1000 bucks is a great deal as long as your guy knows what he's doing. 10 hours seems a bit optimistic though. I did the stem seals myself (not a mechanic) and there is a lot of parts to come off, steps to follow, curse words to say, parts to clean, seals to replace..... Just saying, 10 hours would be very fast if possible.
My0.02
 
#16 · (Edited)
Rahulk, the 545i, 645i and 745i muffler has a valve that closes off one side. At a certain rpm or load level (not sure exactly) the valve opens up and allows exhaust to flow through both pipes. So at idle, it is normal for exhaust to come out only one pipe. The fact that you are getting a puff of smoke after idling for a time is an indication of worn seals.
 
#20 ·
Robz - I forgot about the exhaust switch... And I thought it was only 1 side.

I'll tackle the issue later this year for sure, on a difficulty scale, I'd rank it a 5, doable with the right tools. But there are major risk if done wrong... Dropping parts into the engine, bending valves etc...

Another question, anyone overheat their engine? Usually that is what causes the stem seals to go bad... And from what I have heard, the water pump lasts a long time in this car, like 150k... Or so...
 
#22 ·
How common of a problem is this... And can the job be done with the heads on, on a X5? I got the same problem... The worst thing is I had the valve covers and the upper timing covers replaced last year... An right after the tech told me that the valve stems were fried... I was like, why did you tell me in advance! I would have paid the extra to get the stems replaced too... I'm almost thinking that it should be changed when the valve covers are removed as a preventative measure...
 
#27 ·
The (future) AGA secondary air port cleaning kit will only fix the "secondary air low flow" error message. The fault is generated due to carbon build-up in the heads that clog the port at the exhaust valve. The carbon build-up is due to the leaky valve stem seals. The AGA kit might allow sufficient cleaning of the ports to make head removal not necessary, but at $250 it is about the same cost as removing the heads DIY when you figure in head gasket and head bolt parts cost. Plus, pulling the heads ensure a better job of cleaning than using the AGA kit. IMHO.
 
#31 · (Edited)
Yes you can if your up for a big job. If you plan on doing valve seals then yes you will end up doing valve cover an upper timing cover. If you only plan on doing valve cover an upper timing cover its a lot more work involved to get to valve seals. Ultimately just do valve cover an timing cover until you are ready to tackle or have enough cash to do the valve seals.
 
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