I originally posed this question in the 'Pinging' thread since it was mentioned there that running rich can darken the plugs (https://www.northamericanmotoring.co...ad.php?t=46690) and I am hoping it can be discussed a bit more here since so many people are/will be effected by this.

The Mini software issues with the 05 MCSa have resulted in SES lights, the car running rich and worse (see this thread - https://www.northamericanmotoring.co...ad.php?t=45127).

So, I am wondering, since many of our cars have been running rich for months (had the SES from the first few days of ownership, March in my case) should Mini be replacing the plugs due to build up? Anything else that would/could be affected and should be changed from running rich for awhile?

I did bring my car in ages ago for the SES but so far no-one has contacted me re: the software update by the way Guess its for the best since, from the sound of poor Kellis's post from today the last version (42 I think) didn't fix things for her anyway

Anyway, MINI will do the most cost effective thing for themselves - they aren't even doing a recall - which will be just the sw upgrade, but I want to be sure that the car does not have any related or long term aftereffects of this problem and any information on what could be fouled by running rich and the associated emissions issues over time would be great. TIA

 

Anyone? So everybody thinks its okay to run rich for 5 months and just get a software update?

 

Okay then...

 

I dont have an 05 but i know these cars run rich from day one. My car has always ran rich under WOT. But i have never had a SES light or anything. Its perfectly normal for it to run rich since its a forced induction motor. If u dont run enough fuel u will burn a whole in the piston or cook one of the valves.

 

Odd, I didn't know that running rich was endemic to all Minis. The 03 might have, but its only with the 05 that i know it is for sure (tested exhaust). As I understand it the running rich in the 05 MCSas is at least partially a result of the emissions issues they are having and the resulting Service Engine lights on them.

Perhaps there are degrees that are okay over time or not, for example running a bit rich vs very rich. I just seems to me that having these cars run as they are for so long would have related mechanical consequences (build up on plus/sensors? reduce effectiveness/lifespan of these or other things?) and this is not being address by Mini with their software only solution for most of the MCSas.

 

Most performance cars run rich from the factory, especially cars with forced induction. Running lean will cause the EGT's to run high which can cause detonation as mentioned in the post above. Running rich keeps the EGTs cool and reduces the chance of ping and knock. This protects the engine, but causes more emissions, less mileage and less power. Its a compromise in performnce vs reliability.

 

Okay, I see what you are saying, thanks for the replies. But I guess where I am coming from is that there is a known problem with the MCSas and they are not running normally. Perhaps a bit rich is normal for this car (which I'm not sure really falls into the performance car category, after all reliability for this mass produced car is key) but with the programming problems they are not running to spec/as intended. So based on a car running richer then it should and not intentionally as in your description, what related problems could that cause?

 

Is this an isolated incident? Or does it happen to all MCSa's. A bad O2 sensor or MAP/MAF sensor is a common cause of air/fuel mixture problems. If they are all doing it, then a computer programming or mis-matched sensors would be a common cause.
Does the car run bad? Hows your mileage? It could be the sensors are going off because of bad programming when there really isn't an issue.
Its hard to say... just tossing around some ideas that could cause the problem... The dealer should run a test to see what the AF ratios are . Then they would know more. The plugs are an indication but can be affected by the drivers style of driving...
I drove a MCSa and it drove out fine... It was the only car there in S form for a test drive....
Good luck...

 

From the looks of posts here and MINI2 it sounds like most of the MCSas (at least in the US) are throwing emission related codes and having the SES light up eventually. The light varies and can stay on for long periods or be intermittant, and the symptoms seem to vary a lot - everything from just the light to the car flat out not working (see thread I listed above).

So far it sounds like that for most cars not experiencing a complete meltdown Mini is just doing a software change. I don't think they are checking anything like the AF ratios, etc, I know they didn't when I brought mine in with the SES and I really doubt they do more then plug the car in and dl the software if you go in for the upgrade. That's why I'm asking what could be effected after running the car for months and months too rich, so I can ask them to check xyz (or check myself) and change if needed.

Since it is clear they did such a poor R&D before releasing the cars I feel like I have to take it upon myself to be sure the right thing is done to insure that car is not adversly effected by this and everything lasts as it should.

 

Other than plugs, running too rich can cause carbon build-up on the heads and valves. This can cause pinging as the carbon glows and ignites the mixture at the wrong time. This can be fixed easy enough with the proper cleaners used in the fuel system once the mixture is returned to normal.
Too much fuel can also contaminate the engine oil causing it to thin out.
This happens as all the fuel is not being burned and gets mixed with the oil as it can seep thru the rings. So changing your oil more frequently might be a good idea.
I hope you get this resolved soon so you can enjoy your car! Seems like you might try another dealer to see if they can resolve the problem quicker.

 

cheap way to lean the mixture....

They all run rich, some very, very rich. If you look at dyno post here and other places, about 4500 RPM on they're all worse than 10:1 A/F ratio! Now that's rich! All years.....

If the MCSa has more problems than most, and Mini won't do anything about it, spend the $75 for MTH, get the DSC modified (less intrusive), raise your red-line 200 RPM for fun, and go a little more lean accross the board. Since you have a dyno run with A/Fs, you can probably get a pretty good tune and get more power too..... Mini can't detect MTH, and you can always remap to stock if you want before going in for service....

Anyway, any car that comes stock with over 100 HP per liter is a performance motor, even if it were asked to pull a Buick stationwagon! There's pretty much consensus that Mini/BMW went wayyyyy to conservative on the A/F ratio, and there are some hints here and there that they may have been a bit aggressive on the timing...

So ECU tunes are very, very popular for the modders, as you get a lot of benefit with nothing other than electronics or software. But none of the solutions are inexpensive, and for all of them, the best results is with a dyno tune on that particular car, making it more of a pain because you have to find a tuner that supports both your car and your tuning device.

To make you feel better, there's a reason (actually, about 41 of them) that BMW is on SW rev 42.x Actually, there are many, many more versions, as some had sub-releases.... There were lots of crappy programming items that every version of car has had to deal with, so you're not alone, it's just the issues have changed. To be fair to Mini/BMW, I don't know if any of the issues are due to bad programming, or the fact that they are pushing this little motor pretty hard, and running into fundamental limits of the engine or control architecture....

Done being fair. I haven't seen a stock program yet that couldn't of easily been better than it was from the factory. Our car could be a lot leaner over wide ranges of the RPM band with no risk of detonation, and improved power and emissions. Blew it big time. The car has a knock sensor, so it's already on the edge on timing when hot.... Why not use the knock sensor to prevent issues on a leaner fuel map? Well, no good reason comes to mind.....

Anyway, if you aren't building up so much crap that your combustion chambers and piston tops look like a coal mine, and the plugs aren't caking up with crud, then you'll be fine spitting black crap out the pipe. But a car with a SES light will NEVER pass an emissions inspection.... So you really have to do something eventually.

Good luck, Matt

 

eVal,

I don't have a software update yet...last thing service did (about 3 weeks ago) was to replace the DME. All went well for a while, then about a week ago I had a repeat of the EML, SES, limp mode experience. No problems since then. I'm not sure which software version I have and which version they're recommending. My SA did say that it was going to be 1-2 weeks before the version they want to install is available so I assume that it's something new (?).

Since I'm not mechanically inclined, from all the responses to your questions, would you recommend I ask my SA to take a look at other potential issues that may have arised...also, would you explain what "running rich" means. Thanks!

 

It's chemistry.... (I'm a physicist, but I think I can cover this ). For a given fuel, you need a certain amount of oxygen to burn it. Most of the stuff ends up as H2O and CO2, and a few other things.... Perfect mixture is when you have no left over O2, and no left over unburnt gasoline. For standard gasoline, the perfect air to fuel (A/F) ratio is 14.7. that means you need 14.7 liters of air to burn one liter of gasoline vapor. Running rich means you have more gas than needed (so the A/F ration is LESS than 14.7) running lean means that you have more oxygen than needed. This is where the fun happens.....

Very lean mixtures explode, instead of burn. A healthy burn (and higher octain burns slower) has an ignition point, and there is a burn front that propogates accross the mixture. This propogation of the burn front is good, in that the energy is released a little slower than an explosion, and you can extract more work from it with less stress on the engine internals. When there's an explosion, also called knock or detonation, the whole mixture goes up pretty much at once. And this happens when the piston is at or near top dead center, and there is very little lever arm from the con rod onto the crank. So the energy has to go somewhere, and if it's bad enough, this is through the top of the piston or the side of the block or out the head gasket.

So, if you made it this far you're close to being a mechanic!

So, why not just program the computer to add just enough fuel to be a little richer than 14:7 to one? Say 14:5 to one? This is when you start trading emissions for safety... The extra gas when running rich keeps temps down. It can't burn, there's no oxygen. So it just saps energy from the other gasses to heat it up, reducing the peak temps in the rest of the gas chargeand burn, and it displaces other gasses that can contribute to more energy creation, lessoning the amount of heat to deal with in the first place. This temp effect is good for two reasons. Oxides on Nitroges (bad smog gasses) form at very high cylender temps, and the flash point (self expoding mixture) can be approched at high temps and pressures. The super charger heats the air charge already, the IC helps but doesn't eliminate the heat, and the extra gas is used to control the combustion chamber temps so that it will pass NO emissions, and not ping, detonate or blow itself up.

So Mini has the car running rich, and the MCSa has some different programming for the auto... and it's throwing codes because the tune makes the emissions system unhappy. The right answer is to correct the fuel mixture, but BMW will never do that, because they're the ones that decided what you have now is the best of all possible compramises!

If you're not asleep yet, your a better person than me!

Matt

 

Dr Obnxs, thank you much for your thoughtful posts. When the time comes I will see what comes of the whole thing and what I can determine. I am interested in aftermarket software solutions but at this point I hesistate considering the state of flux the OEM software is at (they can't arrive at a version that is good) and that leads to wondering if the aftermarket stuff is tested with it and will continue to work well with the everchanging Mini upgrades.

Kellis: I would certainly go ahead and ask your SA about it and see what they say (let us know, I'd be curious). I don't know how long/how many miles you had driven with the car in super rich mode (or if it was for sure) so buildup, etc may or may not be much of an issue for you. Its worth looking into though IMHO.

Since I'm no technician describing running rich accurately for you could be a stretch; I did a search to help :smile: Basically, for your engine and associated systems to run optimally there is a balanced amount of oxygen and fuel in the engine. When there is more oxygen than required the system is said to be running lean, and the system is in oxidizing conditions. When there is more fuel than oxygen then the engine is running rich.

Full explaination here: http://www.answers.com/topic/catalytic-converter

 

Add a pulley and intake or something. Use some of that rich mix.