[Nix930]

I have a 2000 M5 with 114,000 miles. Yesterday I let my fiancée drive it while I chased her in my raced-prepared 911 turbo. Each time that she accelerated, I noticed a puff of smoke emit from each tail pipe. The M5 currently drinks a quart of oil every 1,500 miles. Any suggestions on diagnosing or correcting the smoke? Is this normal for a high mileage car?

 

[mottati]

how dense is the smoke? blue/gray or black? I think most M5's will shoot a bit of carbon out of the pipes on hard acceleration. When I wash my car the rear end is covered in black dust, certainly not oily, but dusty. I think that is normal. Your oil consumption seems good, so i wouldn't worry much about it unless the smoke is really pretty heavy.
Mike

 

[ard]

What oil are you using? Castrol TWS 10W60?

I thought, from the title, that it was from the tires...

A

 

[BKH]

Under hard acceleration you may see a puff of darkish "smoke" that is actually unburned gasoline. I suspect that's what you're seeing.

 

[M5_SMG]

Have to agree with the unburnt fuel analysis, unless the smoke is not dark/black.

 

[LuxM5]

Hi,
Did you smell anything ?... If it is burned oil you should have got the following problems when driving behind: little droplets of grease on your windshield, the smoke would have been blueish, and there would have been a specific smell of burned rubber or oil..... hmmm ... this smell should be pretty strong inside the car (M5) as well....

If this is not the case than it should be nothing really (had that on my old Porsche and that were the symptoms)....

Just to be sure, lay down under the car (carefully ) an try to spot any leakage... it should be ok...

Oh... another thing... ONLY use the castrol oil !! nothing else :nono:

I have a 2000 M5 with 114,000 miles. Yesterday I let my fiancée drive it while I chased her in my raced-prepared 911 turbo. Each time that she accelerated, I noticed a puff of smoke emit from each tail pipe. The M5 currently drinks a quart of oil every 1,500 miles. Any suggestions on diagnosing or correcting the smoke? Is this normal for a high mileage car?

 

[Nix930]

Thanks a million for the quick intelligent responses. This is a Great group! The smoke is not dense, not oily and does not smell. I’d guess carbon or unburned fuel.

I usually use Castrol TWS for oil changes, but have used Castrol Syntec 5w50 in a pinch for topping off or for an occasional oil change. Does everyone believe that you get what you pay for with TWS? How often should the oil be changed? Is using Syntec risky?

As far as the comment regarding smoke from the tires, as I’m sure you are all aware, traction control does not help the rubber from evaporating from the rear tires during acceleration. For some reason, I need to add tire pressure every two weeks.

I’m also intimately familiar with old Porsches dumping unburned fuel out of the exhaust. My 930 shoots flames so long that I’ve been black flagged on the race track. However, I thought that the M5 computer would not let this occur.

I purchased the M5 at an auction with 60,000 miles and never performed a scheduled maintenance. It now has 114,000. I thought a valve adjust may be in order.

 

[wilsodh]

I purchased the M5 at an auction with 60,000 miles and never performed a scheduled maintenance. It now has 114,000. I thought a valve adjust may be in order.

To hijack this thread for a moment, have you responded to the Carbon Build-up poll? I don't remember seeing any 114,000 mi '00's in the responses.... :nono: Your high mileage car would be of interest to some board members.

Thanks and cheers,

 

[mottati]

I usually use Castrol TWS for oil changes, but have used Castrol Syntec 5w50 in a pinch for topping off or for an occasional oil change. Does everyone believe that you get what you pay for with TWS? How often should the oil be changed? Is using Syntec risky?.

What is your car's production date? If it's before 3/00 you HAVE to use tws, although an occasional top off probably won't hurt. After 3/00 there was a piston ring design change to 'allow' the use of bmw longlife 5w30. Lots of conspriacy theory about this, as in much of Europe, tws was still used until later models (01 and beyone) and then it was generally castrol slx. At any rate, it's probably OK to deviate from TWS in a post 3/00 car. I recently emailed bmw thru owners circle for a list of approved oils for my 6/00 car. I was told, bmw longlife synthetic, castrol, valvoline or mobil 1 synthetics in 5w30 weight. Interestingly, if you go to the mobil 1 web site and do an oil search, the only oil approved for bmw is their 0w40, not the 5w30 that bmwusa.com suggested....

I’m also intimately familiar with old Porsches dumping unburned fuel out of the exhaust. My 930 shoots flames so long that I’ve been black flagged on the race track. However, I thought that the M5 computer would not let this occur.

I was on track behind a mitsu evo 8 that shot flames from the tail pipe a good 3 feet, that will get your attention! I've never seen it come out of an M5, other than on video games though...

I purchased the M5 at an auction with 60,000 miles and never performed a scheduled maintenance. It now has 114,000. I thought a valve adjust may be in order.

No Valve adjustments are needed on the S62, hydraulic tappets. But spark plugs, coolant, brake fluid, trans and diff oils are always good to replace.
Mike

 

[DavidS]

If you ever see white smoke (not just water condenstaion on a cold day)
it is probably a coolant leak into the combustion chambers. That is very bad indeed.

No Valve adjustments are needed on the S62, hydraulic tappets. But spark plugs, coolant, brake fluid, trans and diff oils are always good to replace.
Mike

Also check MAF performance:

How to test the MAFs yourself and How MAFs work
http://www.m5board.com/vbulletin/showthread.php?t=54788

... there could be some lost HPs to be gained easily.

Cheers!

David