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2009 M6 Coupe 24000 miles Saphire Black
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Discussion Starter · #1 · (Edited)
Hi

Yesterday the B7 started to act reall strange, the engine was running like it went of 2 cyl, it was banging and fireing then letting of the throttle and it did only work( almost) on hight rpms.

Now when the boss finaly got the car home, he had to drive 200 km with the car to get home I had a look at it the next day. I noticed a bolt/screw that was missing in the airintake manifoil ( See pic)

When I put my thumb on the hole the car was running normaly again. Phuuu, I though for a moment that is was the head gasked that was gone again, But the missfireing did make me suspect something else.

Anway, can anyone tell me what that bolt is there for and what dimension it has. ( lenghts ++)

I have tried to make a red circle arond it, it id VERY difficult to see, but it is close the the last A in ALPINA.
It is 2 bolts at that place and I am missing the biggest one. It is a hole straight inside the air-intake manifoil.

I need to use the car on Monday and are wondering if I can use any bolt that fits, or if the bolt has somekind of special "function"

NB! This is a pic from the last problem, it is NOT taken today. So in this pic the bolt is still there, I just cant enlarge the pic to have a good look at it. It looks like the head of the bolt is kind of flat.



http://www.bmwm5.com/photo/data/509/700What_is_this_.JPG
 

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2009 M6 Coupe 24000 miles Saphire Black
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Discussion Starter · #2 · (Edited)
Problem solved.

I found the bolt. :1: It was squiced in between the body and a wire on the right side in the engine departement.

Talk about luck...... cherrsagai

After installing the bolt the engine is running very smoothly......


Erik
 

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Eric,

Great job, but looking at your cyl head, I notice that it looks black! What oil are you using and at what intervals are you replacing it?

The dreaded camshaft wear issue with the M30 engine is caused by loose banjo bolts of the oil sprayer bar. I recommend to check these every time you have the rocker cover removed.
 

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2009 M6 Coupe 24000 miles Saphire Black
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Discussion Starter · #4 · (Edited)
raymond woertman said:
Eric,

Great job, but looking at your cyl head, I notice that it looks black! What oil are you using and at what intervals are you replacing it?

The dreaded camshaft wear issue with the M30 engine is caused by loose banjo bolts of the oil sprayer bar. I recommend to check these every time you have the rocker cover removed.
:confused: embarrising, but to be honest I am not sure what kind of oil we have used this time.

Normaly we have used Castrol RS, and I belive we use the TWS at the moment.

I have to admit the oilchange intervalls was closer together before than at present time.

The engine does not use oil other than the normal. Almost not possible to measure even after several thousand km.....

I agree it look black, any advice to avoid that ?

What kind of oil would you recoment?


BTW: Thanks for the advice regarding the banjo bolts, I will check.
 

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Erik,

I admit that I am using Castrol TWS 10W60 also, don't have that shiny gold finish either, but the cyl heads of my S38 and M88 engines don't look black. I don't have any other recommendation, other then maybe the Motul Lemans 300V 15W60. From what I have understand, this product is a pure esther based (Group V base stock) oil.

Another posible cause of black oil is fuel dillution which is apperant when something is wrong with the ignition or when your injectors do leak. FYI, I recently replaced the oil in my E28 ///M5 and the last 500cc or so that drained out, was completely black, whereas the other 5ltr or so, still was light-brown! The oil was ~2500km old, but had outlived its service life. This ran parallel with the rough running behavior that was caused by a bad/wrong ignition coil.
 

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2009 M6 Coupe 24000 miles Saphire Black
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Discussion Starter · #6 ·
raymond woertman said:
Erik,

I admit that I am using Castrol TWS 10W60 also, don't have that shiny gold finish either, but the cyl heads of my S38 and M88 engines don't look black. I don't have any other recommendation, other then maybe the Motul Lemans 300V 15W60. From what I have understand, this product is a pure esther based (Group V base stock) oil.

Another posible cause of black oil is fuel dillution which is apperant when something is wrong with the ignition or when your injectors do leak. FYI, I recently replaced the oil in my E28 ///M5 and the last 500cc or so that drained out, was completely black, whereas the other 5ltr or so, still was light-brown! The oil was ~2500km old, but had outlived its service life. This ran parallel with the rough running behavior that was caused by a bad/wrong ignition coil.
Well on the time wher this pic was taken in the shop in Germany, the car had leacking injectors and problems with the electronics( motronic box) so that could explain a bit. Those problems had been ther for a long time.
 
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