Dropped off my MINI at the dealer this AM for another windshield replacement, an annoying buzzing rattle in the driver's side door, and the lovely cold start problem...

The MINI serive manager told me that he has been tracking about 100 local MINIs who have had the cold start problem, and has told all of them to use 89 octane gas, and said that in most cases, this has alleviated the problem... odd.

He also told me that he would make sure that my ECU is flashed with the most current version, anyway, but to try 89 octane, and see if it works... Has anyone else heard this before? Does it work?

 

I think your service mgr is nuts. Why run 89 when V37 is supposed to have fixed the cold start problem. All that will do is have the ecu retard timing and cost hp.

My 04 MCS developed cold start problem after about 5500 miles. Have been using 93 since day one and most all my local gas from same place. Have tried different brands of gas and still have cold start. Currently under 7K miles on her so I'll wait for 10K service to get V38 (hopefully V39 to cure YoYo) flashed at that time.

 

I'm not an MCS owner, and I'm not 100% up to speed on the "cold-start" problem, but 89Octane gas does ignite easier than 93 Octane gas, so if the problem is getting the fuel to ignite when trying to start a cold engine, this could help.

On my MC 5-speed, the ignition timing is actually retarded so much during cranking that it is AFTER top-dead center believe it or not. I have recorded 6 degrees after TDC during cranking and 2 degrees ATDC when letting off the throttle and pushing in the clutch from 60 MPH.

 

Running lower octane gas than what's recommended by the manufacturer is a bad idea.

The ECU is programmed to 91+ octane for a reason. Adding forced induction, in this case a supercharger, effectively increases the compression ratio of the engine. Even though the MCS engine is an 8:1 compression ration, you acheive a higher ration with the increased and compressed airflow.

Using a lower octane rated fuel than recommended will cause the engine to knock. Knocking is bad, since it usually means pre-ignition (due to over compressing the fuel) which can damage the engine. Your engine is smarter than that, and does allow for timing reduction/increase to compensate for knock. It's what the knock sensors are for. But, like anything it's usually means that you're going to lose power as well from the timing retardation/increase.

I'd stick with the higher octane gas. It may help that cold start problem, but you might be doing other damage while driving that would be bad.

 

So, consequently, if I run a lower grade of gas... 89... and it doesn't ping, does this, therefore, mean that the engine is running fine?

 

Recently brought in my 03 MCS for a list of minor problems, among which was a cold start issue. The service manager told me that they are having that problem with almost all the MINI's and he suspects the summer mix of gas. He said they would look at it anyways. (I trust this guy, he has been very honest with me). They took the car in and installed the latest version of software, but it still has the start problem. (The stumble is gone though..yeah).

I look at the problem like this, if so many cars are having this issue, it is one of two things, the gas, like he says, or the software. Either way, the dealer can only do what they can. Until a new software version comes out addressing this problem and/or the gas changes, I'll just live with it.

 

Not necessarily. The ECU is programmed to change the timing so it does not ping. So it should sound fine to you. I don't think you'd see a severe decrease in power going from 91 to 89. But 91 to 87 would be more noticeable.

Pre-ignition happens when the gas ignites on it's own due to compression. The higher the octane the less likely this will happen. The MCS engine has an 8:1 compression ratio. At low speeds where the supercharger is not forcing lots of air into the engine the ration stays close to 8:1. But when the charger is cranking the air going into the engine is lots more, and compressed which changes the compression ratio. I don't remember the numbers, it's been a while. You get more power out of engines by increasing the compression ratio, whether by chamber dynamics or by forcing air al a supercharger or turbo. Pre-ignition is caused by the compression of the gas igniting the fuel rather than the spark plug.

It may seem the engine is running fine, but the engine management is supposed to prevent the damage that knocking can do to the engine. So it may be transparent.

And the summer mix of gas could be a problem. Some mixes have more ethanol in the fuel which, I've heard, can effectively lower the octane rating of the fuel. In Cleveland we get 93 for our top end, but some places have 91 for the top grade, lowering that rating even more with the ethanol additive.

 

[QUOTE=mikeoconnor1]Recently brought in my 03 MCS for a list of minor problems, among which was a cold start issue. The service manager told me that they are having that problem with almost all the MINI's and he suspects the summer mix of gas. QUOTE]

That's funny. They said that last Fall too when we had the cold start issue. At that time, they blamed it on the "winter mix" of gas. It seems that someone better get this straight! I never start on the first turn of the key (when cold). This has only begun since early May. I had them reflash last Fall for the same issue.
If their answer is to trek to the dealer each season for a revision...they can kiss my ****.

 

Internal combustion 101... Thanks!

I actually never realized that, cool. Well, not cool, but... eh, you catch my drift.

Anyway. I have noticed for the last several months (perhaps since I started having the cold-start problem), that most gas stations in CT have added signs saying that there is an increased level of ethanol to meet stricter EPA fuel requirements. Wonder if this could be why the problem appeared out of the blue?

Huh...

 

Ethanol "technically" has a higher octane rating, but MINI recommends no more than 10% ethanol. More than that "technically" would void your warranty. It shouldn't be more than 10%, but one wonders what these stricter requirements are.

 

When you state cold start problems, is it when you start your car and the
car stalls on its own a few seconds later? Ive had that happen on my
MCS a couple of times in humid conditions (over 70%RH). I step on the
gas pedal before starting thinking it would change something only in my
head... By the second try she fires up without problems though.


Im on pre v-36 program. I might get that updated this week when I do
the oil change (11k mile service).

 

That is the cold start problem I am talking about, I cannot speak for the rest. I am also in CT so it may be the gas mix, don't know. I agree with bisch, you should not have to reprogram every time the fuel is changed. Our VW turbo runs the same gas without startup problems.

 

Yup, that's it. Never a problem on the second start. Its almost like the fuel stops injecting after initially turning over... weird wild stuff...

 

Its not a fuel problem as many all over the country are having this problem. It is an ecu problem that V37 was supposed to have solved.

 

I've always had cold start stumbles with Sunoco 94 octane, but nothing else does this. Try another fuel before you drop down to 89 octane.

 

I'll repeat again: V37 does not include any new software for the MINI!

MINIUSA is still working on the cold-start issue, which is undergoing beta-testing as we speak.

That said, I run exclusively Sunoco 94 octane. When my car sits for over 8 hours, it almost always stalls after the first crank. It'll always start the 2nd crank, always.

 

That's exactly what I experienced.

 

Exactly the case with my MCS as well.

I didn't have any cold start problem until the car was flashed with v37, which is probably the same as v36 as far as MINI is concerned. That was supposed to fix the occasional yo-yo I've experienced, but guess what? It didn't! As a result, in addition to the yo-yo, I now have cold start every single day.

 

I stand corrected... V37 will not cure cold start problem. Thanks Ryan.

 

Quick BMW Service CD rundown for the MINI:

CD: the actual CD the Service dept. loads on their GT1 Service Computer
V: Version, can be interchanged with "CD"

V31: Basically the first MINI code from '02 through early '04
V32: no change (for MINI)
V33: no change
V34: no change
V35: rudimentary attempt to fix Stumble, worked for most
V36: "the fix" for the Stumble
V37: no change
V38: "the fix" for Cruise control and rudimentary fix for the Yo-Yo (in the process of being released)
V39?: "the fix" for CVT Cooper's? and/or "the fix" for Cold-Start (both of these issues are in-progress, though may or may not make the next CD)

 

Now I'm really confused. I had always thought I had the cold start problem but apparently mine is totally different. My car always needs to go through the first start cycle in the morning before it finally, and always, will start on the second try. Where you say it starts and stalls, mine doesn't seem to fire at all, like it's not getting gas. I've tried to let the ignition run for up to 15 seconds because someone mentioned the fuel pump, switch it off and try but nothing helps. It will not attempt to start on the first try not matter which voodoo method I try. Unfortunately once it has been started that day, it is fine until the next morning.

Well, that is until I stop at a store after driving for a little while it is warm. I have another problem which I have named, hot start problem. It mostly happens after I have been driving to the point where apparently there is a lot of heat under the hood. I can turn the car off, go into the store for 5-10 minutes and when I return, it acts like my version of the cold start problem. Doesn't fire on the first try but works the second time. This problem has never occured when the outside temperature is below 60 degrees.

I've had these problems for about a year now. Even though I have been told MINI is working on an ECU problem, repeated upgrades have not helped any. My MINI originally started with the version put in May of 03 builds, then upgraded to 36 and last May, version 37. After getting version 37, I am weary of letting them upgrade it again until I see a lot of good comments about a new version.

My dealer is out of state so dropping it off for the night so they can be the ones to start it in the morning is out of the question. The only thing I can think to show them exactly what it is doing is go up there in the hottest month and take the service person on a "get the car as hot as I can" drive.

 

SB: My cold start problem is exactly as you described, however; I've never had the Hot start that you described. Just today, for the first time I tried this: Got in car, closed door, put on seat belt, turned key to ON but not to point where starter is engaged. Turned key to OFF then right back to start the engine... it fired right up Haven't driven it since but, I'll try the same procedure tomorrow & let you know if it works again. BTW temp in garage was 70 degrees.

 

Apexer, I'll give that a try tomorrow morning and see what happens here.

The hot start issue is the only one that is affected by outside temperature. Do you have a MC or MCS? I have a MCS.

 

Right after mine was upgraded to V38 the cold start problem went away. About one month later, approimately 600 miles, the problem started in again, go figure

 

If your car doesn't start on the first try, when it is cold, that's a problem. No?
So, then, if you are using 93 or higher, why not try a half tank of 89? It will not harm the vehicle. It will fix the problem, at least for now. Then alternate tanks 93, 89, etc....

91 here in Connecticut is not easy to find, but this solution will work until MINIUSA gets it sorted out.

Try it, you'll like it ! :smile: