I read a response to a question "why are my exhaust tips black?" where Randy explained that the MINI runs rich and blackens the tips with soot. OK, now my question. Does anyone know (Randy, etc) if MINI is working to correct this with software upgrades to the ECU? This running rich thing means there's some performance gains to be had if the correct 14.7:1 mix could be maintained throughout the rpm range. You'd think the emissions would be off with the mixture being sub-optimal. Any thoughts?

 

I think all (newer) cars made by BMW run rich if the engine is cold (probably all european car, I notice the same thing in Benz too). For instance if you start your MINI in the morning, they will run rich at first that's why european engine heats up pretty quick to get the optimal working temprature and then the ECU will adjust itself according to the engine temp. That's what I can think of, any other explanations??

 

That sounds right because you need a richer setting to start the car. However, somewhere on MCO I read that the Siemens ECU "is a work in progress" the implication being that it's not perfected yet. I've also read that some of the tuners have found the car runs rich during normal operation. I guess I'll call MINI-USA and ask them.

 

>>That sounds right because you need a richer setting to start the car. However, somewhere on MCO I read that the Siemens ECU "is a work in progress" the implication being that it's not perfected yet. I've also read that some of the tuners have found the car runs rich during normal operation. I guess I'll call MINI-USA and ask them.

Call MiniUSA for an answer???
I think the only thing MiniUSA knows
is when the next payment is due.

 

OK forget MINIUSA. I found the post where this running rich thing came up...https://www.northamericanmotoring.co...amp;topic=6144. This post and the response in the next post seem to confirm that the ECU is not able to maintain a 14.7:1 mix and therefore we are all missing some horses! The question is can the ECU tuners fix it?

 

The ECU is able to maintain 14.7:1 almost all the time. Only under startup conditions and full load does the mixture run rich. This is completely normal, and all forced-induction vehicles run very rich under load, especially at high rpm. FYI, maximum power is developed with A/F between 12.5 and 14.0.

 

Thanks, I guess there's nothing to worry about then. I'm happy! :smile:

 

Temperature changes can cause any vehicle to run too rich or lean. I ran into this when tuning my motorcycle after putting a new exhaust on. I decided to tune it in nicer weather as that is when I would be doing most of my driving. I don't know if this could be the problem or not as it has only been cold since I've gotten my MINI.

Also I've noticed the ECU in the MINI is very smart. I've even noticed that the tach redline can be changed... anyone know why this is there? does the redline change after the breakin or something?
-Chris

p.s. in case you don't know what I am talking about, there are lighted bars for the redline on the right side of the tach and not all the bars are lit up which leads me to believe it can be adjusted.

 

The extra bars on the tach are for the CVT models, which have a lower rev limit (since with a CVT, there is never any reason to rev higher than the horsepower peak).