A "cold start" refers to starting an engine after it has sat for a good period of time, typically long enough to where it's dissipated all heat since the last time it ran. So, every morning that you crank the engine for the first time, that's a cold start.

It has nothing to due with the ambient temperature of the garage. Other than taking longer for the the oil and water to come up to their operational pressure/temperatures, given your location at the North Pole.

Conversely, if you were to crank the engine a couple of minutes after shutting off a car that had been driven enough to bring the fluids to their nominal ranges, that would be a "warm start". Even at -20F ambient air temperature.

Cheers,
JnC

 

I can't speak for MINI's system exactly, but I've been on the development team for several EGR, MAP, and oil pressure sensors, most of which we sold to Ford.

In Ford's system, the sensors (we would be talking about the MAP sensor here) has to return a signal within 1/10ths of a second to the computer as soon as the key hits 'on'. The idea is that by the time you turn the key to start the car, it already has gotten accurate readings from the Manifold Absolute Pressure sensor, which is at that time atmospheric, which it will then use for all calculations that follow.

Here's something I may have asked before but forgotten. Does the new MINI engine use the 'oil pressure on demand' system like the new BMW motors do? If you don't know, some new BMW motors have an oiling system that uses an oil pressure sensor to control an electric oil pump. This gets the oil pump off of the main belt, reducing parasitic loss on the drivetrain.

We were working on the development of the BMW sensor when I was at Honeywell. I could see the potential for that sensor to have response time issues.

 

I'm not 100 percent positive, but I do remember reading something about the prince engine having an oil pressure on demand oil pump.

 

If that is the case it could be related. Although I think the 135 and 335 have it as well, and don't seem to have any issues, the sensor supplier and style could be different.

One of the issues we were working to resolve when I left Honeywell was that the sensor, which was an absolute sensor (has a sealed volume on the die so that it does not change reading when atmospheric pressure changes) had a slow response time occasionally.

It is POSSIBLE (I'm completely speculating here) that when a cold car is started and run for a short time and stopped, the sensor channel fills with cold, thick oil, and that cold thick oil doesn't have time to drain while the car wash or whatever is happening.

Then, the second time the car is started, the oil pressure sensor is reading a slightly higher pressure than it should, so it demands less oil from the pump, and the issue occurs. Once the oil warms up, it flows freely through the sensor channel, and things work normally.

This would explain the recommendation of 0 weight oil, as it will flow better when cold.

So, that above explanation makes sense given the circumstantial data in this thread. However, the MINI may not even have the sensor that I have described, nor may it function in the way I have described. So, again, I'm guessing here, but maybe someone more knowledgeable about the engine can fill us in more thoroughly.

 

If only MINI would not keep concerned and knowledgeable people, such as yourself, in the dark! I wish there were some way to convey your thoughts to people at MINI who are willing to listen.

 

http://www.motoringfile.com/2008/07/...comment-227348

 

BMW software strikes again! Guess it takes a rocket scientist to figure out that a cold engine needs lubrication. People have been speculating all along that it was an oil starvation problem - can't believe that it has taken BMW this long to officially acknowledge the issue. I can imagine the extra wear and tear this caused on the engines affected by this issue.

 

This is just stupid!

I have been toying with the idea of trading my mini in. Now I think I will!

 

I'll be pleased if all that is required is a software update; I wouldn't want the dealer ripping apart my entire engine if/when a fix arrives.

 

I agree with this statement. Overall, this is great news that something is going to be done. I'd love to hear MINI state they are going to add some additional warranty to the drive train to the people who have this problem.

 

Who knows how much damage is being done when the engine does it's cold start hammering? A sound like that has to be damaging something.

Now lets hope they find that fix soon & they do extend the warranty a decent amount. Nice that they've admitted there is a problem. Seems as though the line that "oh it's normal" was just a lie. Hmmm....

 

I doubt BMW/MINI will extend the warranty since the past 2 times that I can remember them doing it was when the engine would suffer a catastrophic failure.

Nikasil V8 engines from the 90's, affected e34, e32, possibly e31 i'm not sure. both 3.0L V8 and 4.0L V8. BMW extended engine warranty to 100K miles.

M3 S54 bearing failure. BMW extended warranty to 100K miles and also replaced the bearing as part of a service bulletin.

Both those cases had many many documented incidences of complete engine failure. Do we know how many engines have failed due to the cold start chatter issue as of yet? It would help (IMO) strengthen the case for an extended warranty if there are significant number of them documented.

 

Good Day:
I didn't read all of the threads buy how about:
http://www.bmwz8.us/pdf/zz-VANOS_s62.pdf

Cheers,
Brian

 

Hi everybody!

As you may know, the engine in our R56 mini coopers won the "International Engine of the year award". I looked up in the internet and found their website ( http://www.ukipme.com/engineoftheyear/ ), and decided to send them an e-mail as a way to let the media know about our problem and put more pressure on Mini/BMW to fix it. I will post my original e-mail and afterwords their reply.

Subject: Congratulations on your terrible choice.

Here are a few samples of how your research for the awards is not sufficient. Your so called “engine of the year” in the 1.4-1.6 litter category has a major design flaw that, so far, BMW can’t fix.

Please check the following links and the file attached.

https://www.northamericanmotoring.com/forums/showthread.php?t=130512

http://www.mini2.com/forum/2nd-gen-faults-fixes/136105-mini-cooper-s-engine-noise-when-cold.html

http://www.r56mcs.com/

(I removed the links to youtube so that the videos won't show in this post.)

Hope the information will be useful for future selections, and maybe a rethinking of this year’s award.

MP
Mini cooper S owner

Here's their reply:

Dear Moises,

Thank you for the email. The International Engine of the Year Awards is now in its tenth year and it has proved to be a major success for car makers and automotive engine manufacturers around the globe. The winning powertrains are selected by 65 highly respected automotive journalists from 32 countries. As well as involving the voluntary participation of our judges, UKIP Media & Events - the company behind the International Engine of the Year Awards - receives no advertising or financial support from any car manufacturer or distributor. The Awards are fully independent and the winners are selected by our experienced and very knowledgeable judging panel - people that get to test drive all new cars and engines around the world. If you wish, I'd be more than happy to send you this year's International Engine of the Year Awards magazine, which not only will provide more detail in how the winners are selected, but it also includes a breakdown of each category; what the judges thought about each engine; and scoring/league tables.

Kind regards and many thanks

Dean


The reply you just read was copied by the writer to four people inside the same organization, so I think that at least some people in the media are now aware of the problem. Let's see how far it goes. I replied again, I will post it as soon as I get an answser.

 

want to add my car to this thread as having the same issue.

each time was after moving the car for a short distance, then starting it later.

2 times was after washing the car. driveway is on an incline.
3rd time was after moving it out of the garage to get to my lawn mower..

Sound goes away after a few rev's and or driving down the road about a 1/4 mile.

I havnt read anything else, but I will add that my exhaust has pushed out some REALLY black liquid on one of the times. But i "think" i may have sprayed water from the hose into the exhaust while i was washing the rear of the car. This was after the first time i heard the noise. Really black liquid spewed out of the exhaust. I shut off the car and checked the oil. It was the natural brown color like you see with new oil. So that lead me to believe it was hose water i had sprayed...

Car now has 2400 miles on it.

Temp has been as low as 72 degrees and as high as 90+ degree's with these occurances.

 

Hey!

Today I picked up my mini from the dealer. They kept it for two weeks to fix the diesel like noise. In my case, the noise was permanent under 3000 RPM. They changed the chain tensioner and so far (picked it up and drove 8 miles) it sounds like new.

The dealer took two weeks to fix the problem because they had to order the parts from Germany.

Any further issues I will keep you posted.


Regards

 

oops

 

My 2009 MCS-a was eight days old yesterday (276) miles. My wife and I both noticed the clattering (diesel-like) when starting it. I let it idle for 30-45 seconds, then drove away slowly. The noise continued, so I pulled over after 200 feet or so and turned off the engine. When restarted, the noise was gone.

Interesting observation from reading the posts below: we live on a busy street and parallel park in front of the house. I move the car forward or back when I notice others have parked too close and may scrape the MINI when leaving.

I had done that the previous day on two occasions, prior to the clatter yesterday (i.e., I had started the car, moved it forward or back 3-5 feet, then turned off the ignition. It was on no more than 30 seconds each time.)

Sounds very plausible that the noise could be associated with turning off the engine before it has had a chance to warm the oil, then turning it on again later.

 

^^^ just so you know if you only want to move it a few feet, and not on a hill, these things are really easy to push from your door. Sometimes if I'm not all the way in my lines on a curb parking space I just pop it in neutral (you can to the same with the auto) and drop the ebrake and just push if forward or back a little with very little effort

 

Thanks, I'll try that. My MINI is still so new I'm kind of obsessive about trying to avoid fender scrapes.

 

Correlation here. Yesterday I moved my 07 MCSm 50 feet from where I was doing some home repairs, and I got the clatter next time I started. I hadn't heard it since June.

Now if we only knew what that meant . . .

MINI USA, would you please clue us in?

 

Oh yeah trust me that doesn't go away haha I have a special parking spot when I go to work and it has a grass and trees to one side, and a marked off no parking area on the other for the handicap parking spot next to it to unload. No body can park directly behind or in front either.

 

My 2008 MCS 6spdMT did it once with ~1200 mi on the clock. The day before it happened... I backed it out of the garage, washed it and drove it back in the garage. In total the car was running less than 30sec. Since then, no more quick starts/stops. If I have to, I'll drive it around the block. Haven't heard it since, have over 3500mi.

I had an Audi that acted the same exact way.

 

Yes, I can do this with my automatic,
but only because it was a March '08 build with that faulty transmission 'lock'
that you see complained in the thread here "Amber Gear icon showing...

I do find it handy and am in no hurry for that fault to be corrected.

 

Stupid MINI, she has been very bad lately and the death rattle is actually least of my concerns. She has taken a liking to not starting well when cold.
Here is a video of her death cough.....Ie rattle she sat for 2 days and it was 65 degrees out. http://www.youtube.com/watch?v=TpJxH7Dns3U