Just a thought here: perhaps the OP or someone else could take a survey and post the results. Just how many affected so far? Given this thread and the one on MINI2, it seems like there are quite a few.

 

I'll throw my theory on here as I've yet to hear anyone bring it up on this thread,
I read at least two individuals report that they get the sound when they start their motor, they immediatly shut it down only to restart it again. But on the restart the sound is gone and all is well.
To me, this sounds like some sort of software issue if the problem is fixed simply by 'resetting' the computer/ECU.

Another point I would like to add after reading all 12 pages is to ask if this problem has been directly linked to ANY kind of damage to engine? The motor that msh411 sent back to the UK should show SIGNIFICANT wear to all the parts, right? but if not, then why all the fuss? start your car, if the noise goes away eventually, wait it out or give it some gas to speed the process up and be on your way, if your motor blows up, I can only assume that MINI would be happy to replace it for you.
$.02

 

So when you finally get that hot date with the person of your dreams and you start your car and it sounds like it's falling apart even though you just paid $30,000 for it, your OK with that ?

 

from what I've read, heard and talked to people about, there are possibly several issues all that have symptoms that show up on cold start. Engines have been replaced, tensioners have been replaced, and I've yet to see any global fix for what's going on. It's some engines only, not all.

For what it's worth, I don't think they have a good handle on this yet, as a brand new Clubman was sounding less than idea at the CLubman release this weekend.

Watching with interest...

Matt

 

I don't think were necessarily talking about different problems, per-se... I think more accurately we might be talking about several symtoms with the same singular cause.

If the oil is not viscus enough... or its not pumping through the circut effectivly... or has air in the oil circut... we're going to see the symtoms effect everything that depends on oil pressure for proper function.

 

I have to agree that these may be different issues, did anyone else notice that the engine sound in some of the videos listed on page 3 sounded significantly different? even after taking into account the different video qualitys, etc they still sounded slightly different-anyone else pickup on that?
Perhaps people here are having different issues mechanically

 

I've read the complete thread on the Michigan Mini site on the lifters, and the author has a number of really good write ups, and it would be convincing to me except for one problem... the same lifters are used in both Cooper and S (part# 11337549632), but the problem seems to be only in the S, right? If it was the lifter, we'd see this problem roughtly in the same proportion to sales of Cooper v S.

Great write up otherwise, and very informative for how the Hydraulic lifters work.

 

If the cooper S uses more aggressive cams (ramp rate, duration, etc) compared to that of the cooper, it could cause the lifter tick.

Just a quick update, the engine in my MCS is very smooth in the morning since the change over to Castrol 0w-30. It even seems like the initial start-up hum or buzz has quieted down. Could be the placebo effect, but the engine does feel smoother and seem quieter in the mornings. It was 33 degrees today and I heard nothing abnormal.

 

My uneducated guess - R56s has an Oil pump that pumps only when the computer tells it to so the engine will run as lean as possible . Either some pumps are faulty or the computer is cutting it so close that it's favoring lean fuel consumption over engine running without harming itself .For those of you who change your own oil , it has that starved for oil sound any car makes your first start after oil change , only it's 2 minutes instead of 2 seconds .
Maybe we can start making bets on how this turns out .

 

The oil pump is not computer controlled, and has absolutely nothing to do with how lean or rich the engine runs. You either have oil, or you don’t. The volume of oil that the pump moves is dependent on the RPM's of the engine and other mechanical means. Generally, the faster the engine is moving the more oil is pumped. That's why it's called "flow controlled". You wouldn't want an something that is electronic go bad and destroy a $5000+ engine when it can be done with cheap and effective mechanical systems.

1. oil pump
3. Drive chain

http://www.realoem.com/bmw/showparts...28&hg=11&fg=30

From RealOEM.com

 

For even greater pleasure, Mini again offers the Cooper S, with a turbocharged engine that uses direct injection and gets a new cast aluminum block. Among other features, the oil pump works only when needed and an on-demand water pump is installed. Rated 172 horsepower at 5500 rpm, the Cooper S engine puts out 177 pound-feet of torque. EPA fuel-economy estimates are 29 mpg in city driving and 36 mpg on the highway.
http://www.tirekick.com/TK06-May/07Mini.htm
terms of both power, performance and efficiency, these innovative drive units set new standards in the MINI segment, boasting many design features and technical details so far only to be found in higher segments of the market. A volume flow-controlled oil pump, for example, as well as a water pump switching off automatically when not required, serve to reduce fuel consumption to an even lower level than usual.http://www.topspeed.com/cars/mini/20...s-ar11301.html
Helping to improve the fuel economy of these stronger engines are water pumps that run only when necessary, and variable-flow oil pumps. With its silky Getrag six-speed manual transmission, the S model carries a federal rating of 29 m.p.g. city, 36 m.p.g. highway, versus 25/32 for the previous model. (The base model does even better at 32/40 m.p.g.). Premium fuel is recommendedhttp://www.nytimes.com/2007/03/18/automobiles/autoreviews/18AUTOS.html?ex=1331870400&en=79ea763e93aadc0d&ei= 5088&partner=rssnyt&emc=rss for both engines. http://www.nytimes.com/2007/03/18/au...rssnyt&emc=rss
Both engines are mated to six speed transmissions--manuals are standard with paddle-shift automatics as an option. Fuel consumption is decreased by up to 20 percent compared to the current Cooper. Part of the credit is due to electronic steering along with trick water and oil pumps that deliver only as much pressure as needed.http://www.automobilemag.com/future_...r_s/index.html

 

Did anyone catch this article on Motoringfile? It showed up in Google reader, but when I clicked through to the article it did not exist on Motoringfile.com.

 

It showed up my RSS reader as well and was 404'd on motoringfile. They seem to do that quite often. The story will probably show up tonight or tomorrow morning if prior history proves correct.

 

One of BMW's technological claims for the R56 was volume controlled oil flow. While RealOEM shows an oil pump, it does not show the exploded view to see how it works. Most automotive pumps are scavenger pumps that sit in the pan. That's obviously not the design in the picture.

From the service manual:

Oil supply

Oil supply

The oil supply in line with requirements only delivers the amount of engine oil that is actually needed. The volume-flow-regulated oil pump lowers fuel consumption by up to 1 %.
Brief description of components

The following components are described for the oil supply:
Oil pressure switch

The oil-pressure sensor signals to the DME control module whether there is adequate oil pressure in the engine (switching point 0.5 bar).


Volume-flow-regulated oil pump
The engine has a volume-flow-regulated oil pump. This pump supplied exactly the amount of oil required by each operating range. The oil pump is an external gear pump. The oil pump is driven by a chain from the crankshaft.

 

So then a slightly higher oil ressure switch, say .6 bar, might cause the oil pump to raise oil pressure just enough to fill lifters sooner and protect slightly better than spec? Race shops carry oil pressure sensors that trip dash lights at lots of different pressure readings... could it really be that simple?

 

This is an interesting development for sure. At my previous job, we were developing an oil pressure sensor for BMW. Technically, our German engineering team was designing it, based on a few designs we in the US had in production for EGR pressure sensors. I was involved with quite a bit of the design reviews for the oil pressure sensor, but I don't think it was at that time (this was 2005) slated to go into a MINI, but I'm sure they're using a similar technology.

I could tell if it was the one we designed if I saw a picture of one, I guess.

If anyone wants to test it, the sensor will probably have a 0-5 volt output. You could put a meter on it and start the car, and see if when you get the bad sound the output from the oil pressure sensor is different than when you don't get the sound.

 

http://www.motoringfile.com/2008/02/...issue-exposed/

 

It's really good that this made MotoringFile. I hope that this gets MINI's attention. I've got an 800 mile 2008 week 2 MCS and I'm keeping an eye out for this issue.

 

If any of the doubters can listen to those video's and tell me there's not a problem you're opinion is pointless.Even if it's doing no damage the sound is ridicules for any car to make .

 

This videos are very helpful. You can clearly hear the difference between the direct injection noise and the cold start rattle.

 

The motoringfile really didn't explain anything. It was more of a summary of what has been said on here and MINI2. If anything, it was able to get Mini of North America to notice.

Like I said originally, this is an oil/lifter problem. I've had experience with this in my past car, an Evolution VIII. The 4G63 was always a noisy engine. Once you added aggressive cams with longer durations and taller lobes, the lifters became even more noticeable particularly at start up. When I changed my oil from a 10w-30 to a 5w-40 the lifters would tick even at idle. It was almost embarrassing because the tick was so loud. I remember being asked several times if there was something wrong with my car. I always responded to them that "it was cam'ed to death."

This may be why only the MCS experiences this effect, because the cams have a more aggressive profile than that of its MC brother. Aggressive engines are slightly noisier than other engines. They tend to work on the edge of reliability. It's no small feat to have a 1.6L 4-cylinder to have the same power that some V-6's had only a few years ago.

For now, I've been running Castrol 0w-30 (BMW LL-01 approved, A3/B3) oil in my mini for almost a week. In the past two mornings it has been around 30 degrees. If anything, the engine starts are smoother now and seem quieter than before. Does this mean anything? I'm not sure. So far it has seemed to help. Only time will tell if "the noise" comes back or not.

 

I agree that the noise is quite clear. This is a very troubling issue and a real one despite the doubters. Kudos to Motoring File for taking up this issue. I look forward to hearing from MINI as the same engine sits in their newly launched Clubman.

 

Won't 0w-30 hurt your engine, since 5w-30 is spec'd in the manual?

 

I've almost convinced myself that my cold start noise, though it's very similar to that posted and described, is the throw-out bearing. It happened again yesterday, when I had a witness. Clutch in, sound goes away. Clutch out quickly, it almost goes away. Clutch out slowly, it gets horrible. Since I've now got another issue, I'll bring it up when I take it in.

 

No - nothing to do with the clutch. I've sat it out and let it go away, and I've driven away while it was still clattering - clutch has no affect on noise. Warming up makes it go away. Sometimes its 2 minutes, sometimes 30 seconds.