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Discussion Starter · #1 ·
Hello,

I recently purchased a 2000 M5 with 86,000 miles. I knew it burned a little oil when I purchased it; however, the problem is worse than I had thought. The car goes through a liter of oil every 360 miles or so, and only gets about 250 miles to a tank of gas due to the massive blow-by. I can probably live with the fuel/oil consumption (although my wife won't let me roll down the windows the fuel smell is so strong). Does anybody know if this is a sign of impending engine failure and a need to move the car quickly, or am I just going to be inefficient, smokey and stinky for the next 2 years?

Thanks
 

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Thats not horrible abnormal for a MY00 considering yours is more than likely a pre 03/00 production date. The pre 03/00 have low tension rings and will consume more oil than the 03/00 + model years. Mine consumed a similar amount of oil, I do believe mine is strongly related to valve stem seals as engine braking really increased the consumption. When i cut back my engine braking, my consumption went from a liter ever 500 miles to every 1500-2000 miles. Hard to gauge because i change my oil every 1500-2000 miles anyways.
 

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Thats not horrible abnormal for a MY00 considering yours is more than likely a pre 03/00 production date. The pre 03/00 have low tension rings and will consume more oil than the 03/00 + model years. Mine consumed a similar amount of oil, I do believe mine is strongly related to valve stem seals as engine braking really increased the consumption. When i cut back my engine braking, my consumption went from a liter ever 500 miles to every 1500-2000 miles. Hard to gauge because i change my oil every 1500-2000 miles anyways.
WHAT?!?!??!

That is abnormal and cannot be considered close to normal by any stretch of any BMW criteria. BMWs guidance is one quart per 600 miles, OP is at twice that.
 

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Why does everyone always think it is piston rings only responsible for high oil consumption.......

Remove the plenum cover,see if there is loads of oil.
Look in the air filters if there is oil....


Most of the cases I see with high oil consumption on early cars is either Vanos O-ring issues or clogged bores so the pressurized is released in the plenum,bad oil separators or valve shaft seals leaking....

I would also check the engine from the outside for oil leaks from valve cover gaskets,crank sealings,oil pan....

A compression and leak down test reveals the condition of the piston rings.
 

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Discussion Starter · #5 · (Edited)
Why does everyone always think it is piston rings only responsible for high oil consumption.......

Remove the plenum cover,see if there is loads of oil.
Look in the air filters if there is oil....


Most of the cases I see with high oil consumption on early cars is either Vanos O-ring issues or clogged bores so the pressurized is released in the plenum,bad oil separators or valve shaft seals leaking....

I would also check the engine from the outside for oil leaks from valve cover gaskets,crank sealings,oil pan....

A compression and leak down test reveals the condition of the piston rings.
Well, the rings assumption is based on the fact that I've got both an oil issue and a fuel issue. I think I can rule out an oil leak since there is no evidence of oil on my garage floor. It is certainly possible that I have separate, distinct problems for both issues; however, bad piston rings explains them both and is not an uncommon problem in this car. The dealers are horrendeously expensive out here, and the on-the-cheap mechanics in the industrial district likely don't have the expertise to properly diagnose, more of a remove/replace trial by error solution which will do nothing but waste money if it is indeed rings.

I do engine brake a lot, I will try and back off of that on my next tank of gas/oil replenishment to see what difference it makes. When driving behind my own car, I only get the thick black smoke under hard acceleration, can't really come up with a repeatable reason to get the white smoke.

Assuming it is bad piston rings, still trying to figure out if this problem will rapidly degenerate into a blown motor or if I can continue to drive the car with the added fuel/oil expense.

Thanks
 

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Pardon my ignorance but is oil/fuel expense really even an issue in a place like Abu Dabhi?
 

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Don't you have to do a compression test to see ifhte rings are really bad or not ? I would do one for peace for mind and/or to prove/disprove your theory

Also BMW's specification for maximum oil consumption is 416 Miles per Litre, for the S62 Engine.

If it was my car, I would first change the oil separators and vent hoses, if not already, and also IDEALLY the drain pipe to the sump from the separators (difficult access to this though).

As Raikku says, check the air filters for oil and remove the plenum lid and see what its like in there, if its full of oil, then there are known causes for this, and could be your issue.

Also your smell of fuel could be even an exhaust leak right ? I wouldn't jump to the conclusion of bad rings by combining the strong smell of fuel and the high oil consumption.

Do you have any fault codes ?

Good Luck
 

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Getting black smoke is a clear sign of too much fuel being dumped in the engine. It has very little to do with the oil consumption. The amount of oil usage may be slightly related, based on the load of the engine. I think you need to get the fuel problem fixed first and continue to monitor the oil consumption.

Listen to Vantaam5! He is very knowledgable and brings a great point about checking under the plenum.

I'm just speculating, but if the throttles and sensors are choked with oil and carbon they probably don't function as well as the should causing you to have to push the pedal more to get good power. If I remember correctly, didn't you state in another post that you didnt think it had all the power it should? --- These problems would be a good explanation.
 

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Yeah as long as it's cheap who cares about the excessive pollution? :sad3:
I was simply responding to his comment about putting up with the cost of fuel and oil..get it
 

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I think I can rule out an oil leak since there is no evidence of oil on my garage floor.
If you truly believe this, then you definitely need to pay a specialist -- despite the fact that you could get a Peake and follow the advice vantaam5/M5London.
 

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What I wrote is a general trouble shoot that is easy,does not take loads of time and rules out systematically parts responsible for the problems you got.
If you remove the spark plugs for the compression test,you see if they are wet with fuel on individual cylinders or all cylinders.
Checking for oil leaks means the undertray has to come off,just because you do not have oil spots on the floor,this does not mean anything...

The smell of fuel can be anything,like a real fuel leak,O2 sensor issues(including cracks around the bunge),t-stat,leaky injector,......

Before these things are checked,guessing what might be the issue you have is senseless and a waste of time.

Don't want to sound like a d**k,but I think I know a bit about these engines...:biggrin:
And this is how I would trouble shoot:

-Plenum cover away,takes 10 minutes time and a 10mm socket.See how much oil is in there,best post up a pic.
-Also an error read out as M5London said is for sure needed.
-Compression and leak down test.This shows the condition of the plugs(post pics and we look together at them) and if the piston rings blow by...
-open the air filter boxes and look for oil in there(takes about 5 min,no tools needed)
-Check for oil leaks from underneath,under tray off(20 min,Phillips head screw driver needed)
-Check when the car is up for fuel leaks on the driver side floor.
-Check when car is up the bunges of the O2 sensors for leaks.
-Check when car is up if the O2-sensors are connected correctly,means not to each other(very popular issue).

Report back.


You can take this advice or leave it..............

All this is easy non time consuming diagnosis to find your issues.
And something even a back yard mechanic can do without screwing things up.

Might be easier and cheaper that way to check things out,before tearing an engine apart...
 

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Discussion Starter · #13 · (Edited)
Thank you for all the replies, this is great information and you've given me some hope that it could be something less devastating than real engine trouble. I know you regulars probably get nubs in here all the time that want the quick easy fix, you offer advice and it's not heeded. I promise I'll investigate these things, but believe it's not as easy as described due to a few challenges I've got in front of me.

Most houses out here don't have garages, including the one that was contracted for me so I was advised not to bring anything that I would normally put in a garage. This means no jack stands, jack, air compressor, or any other "heavy" type tool I'd normally have. I've also been here for > 2 months and my household goods have not yet arrived (nor does anybody know where they are). This means my entire collection of tools is a $2 screwdriver I bought at Carrefour until my own arrive at some unknown time :).

So, great advice, but please don't give up on me when I don't immediately report back with pictures (yeah, no camera either...).

Thanks!

EDIT: BTW, I do realize that in an earlier post I said no oil on the garage floor and here I say I've got no garage. My previous post was basically just being lazy and calling my car port a garage. I doubt I'll ever stop calling the place I park my car a garage, but I wanted to clarify.
 

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First off, I'd suggest that the oil consumption and excessive gasoline consumption are unrelated, although it's very likely that the oil consumption has fouled sensors and such, thereby causing the excessive gasoline consumption. I would follow all of vantaam5's suggestions.

Secondly, I'm curious about the OP - where he's from, why he's in Abu Dhabi and why did he select such an expensive car to maintain while living in a foreign country with no tools and (apparently) no decent place to have the car serviced? I'm guessing that he bought the car there, probably on a whim. No matter, but I was curious.

Best of luck. Try to resist the temptation to dump the car and get a Toyota, and least not until you figure out what's wrong.
 

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Discussion Starter · #15 · (Edited)
First off, I'd suggest that the oil consumption and excessive gasoline consumption are unrelated, although it's very likely that the oil consumption has fouled sensors and such, thereby causing the excessive gasoline consumption. I would follow all of vantaam5's suggestions.

Secondly, I'm curious about the OP - where he's from, why he's in Abu Dhabi and why did he select such an expensive car to maintain while living in a foreign country with no tools and (apparently) no decent place to have the car serviced? I'm guessing that he bought the car there, probably on a whim. No matter, but I was curious.

Best of luck. Try to resist the temptation to dump the car and get a Toyota, and least not until you figure out what's wrong.
I'm US military, most recently Phoenix but I've been lots of places. I was torn in my buying process, plain jane boring econobox that I wouldn't have to spend any money on or a larger sedan that I'd at least find interesting (and where I might survive a crash, the drivers out here are terrible). I owned a brand new e46 M3 while stationed in Germany and loved that car more than any other vehicle I've ever owned and when I found an apparently clean M5 for sale at a good price I couldn't help myself. I will have a good set of hand tools eventually, they're just taking their sweet time getting here.

I could get the car serviced in Dubai by an independent BMW service provider but they're certainly not cheap, and it's >1hr drive to get there so not really convenient. On a new note, those who guessed there could be an oil leak were correct. I did not realize that the undercarriage cover would hold oil for any length of time, but just today I got my first spot on the floor. Doesn't mean the car isn't burning oil -- I've seen the blue/gray smoke, it just might not be burning it as fast as I thought since it appears to be accompanied by a leak.

To the reply who asked about the power of the car, I think I said in a previous post that it didn't compare to my "old" M3. It certainly feels slower than a 400hp car should, but I just attributed that to it being 10 years old and didn't think much of it.

EDIT: I did have a chance to check the air filters -- both bone dry.
 

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Good that the filters are dry!

If you need the contact details of a good indie BMW shop in Dubai,let me know!
Know some guys that might be able to help you!
 

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Discussion Starter · #18 · (Edited)

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Wouldn't 250 miles to a tank be about right anyway? About what I get for exclusive town/city/traffic only driving, if not just a little more.
 

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Wouldn't 250 miles to a tank be about right anyway? About what I get for exclusive town/city/traffic only driving, if not just a little more.

Thats about what I recently got. 263 miles before the Low fuel light came on, all city/town driving and 3-4 MAF test runs.
So I would say 250 is ABOUT right
 
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