The MCS stumble page (here) has grown to 6 pages, so rather than bury a post down in that I thought I'd bring this up in a new thread...in the more general mechanics area where perhaps more members are apt to read (the other thread is in Performance Mods).

As the weather has warmed, I think that the low end performance of my 2002 MCS has deteriorated below its already rather pathetic levels. For the record, I do not have any modifications (pulley, intake, exhaust) and I HAVE had my software unfortunately upgraded to 33.2. This "upgrade" caused the 2000rpm stumble and long cranking/stalling on a cold engine. I'm thinking that it also has begun to cut into low end performance.

In the past two weeks, my car has felt like a DIESEL (in terms of acceleration) at anything below 2500rpm. I have often found myself completely flooring the accelerator at these low rpms and I get a phhhhhhtttttttt pickup. But of course, once it gets over about 2500rpm and the supercharger kicks in, I fly.

So, I'm wondering what others have experienced. If you have an MCS, without mods...

1) What's your impression of low end performance?
2) Has your car "changed" in terms of performance with the advent of warmer weather?
3) Have you had your software upgraded and/or what's your build date?
4) Do you notice your air conditioning having a negative impact on power/acceleration?

Thanks for the data!

 

JSUN:

I took delivery of my MCS this past April and, like you, have not added a thing. Cold start: MCS starts on second attempt every time. When starting out in first gear, I keep thinking I'm still learning MCS's clutch sensitivity...but, I maybe deceiving myself as she probably has low end issue. Once we get going, everything else is fine.

I'm hesitant to bring this to dealer's attention as I've read other posts, like yours, stating the upgrade made things worse. I would take your MCS back with the issues you've stated. Hope that helps!

_________________
MCS, PS/Black Roof & Mirrors, all 3 packages, 17" perf. tires/8 spoke, HK, anthracite, two-tone cloth seats, bonnet stripes "GRRRRR." Delivered 4/15/03. Awesome!!!!!!!!!

 

So Scoobs, basically what you're saying (as I interpret you) is that your car has the same issues as mine. Maybe I've just dealt with them longer and have developed a decreased tolerance.

BTW, starting on the "second attempt" is absolutely NOT normal MINI behavior!! My car always fired up strongly and immediately until the software upgrade.

 

JSUN,

Even though you may not want to, take your car back to the dealer, when they upgraded my ECU to 33.2, I went back and complained about the abysmal performance and according to the dealer the programming "did not take" and they had to clear some trouble codes and redo the programming, world of difference in the performance. This was before I added any mods to my car and I've had no issues other than a bad O2 sensor which was replaced under warranty last week. I wish they would load the JCW programming, which is better suited for my modded car, but I haven't been able to convince anyone there, next time my car goes in for service, I'll see if bribing the tech works.

X2

 

jsun,

What part of the country are you in. I just want to try to rule out some of the things MINI has been telling us. Bad gas, extreme temps da da da. I live in the Dallas area.

Graham

 

Hmm, I gotta try that, I get all of the above sympoms, and it's getting worse by the day..

 

jsun: I edited the title of the tread to make it more clear this was about the stumble issue you guys are having. I hope MINI gets you guys fixed up soon.

Dave

 

Here's another thought. In all of my reading of the stumble thread in perfomance modifications, I don't recall anyone ,with the exception of someone in Canada, reporting a stumble from anywhere but the US. Do UK cars stumble, what about German cars? Can we get some input from someone in Europe?

 

I'm in the Boston, MA area. My service guys (MINI of Peabody) are generally great, but they've been stumped - so they say - by this stumble and/or poor performance issue. They claim that they have a number of customers complaining about this and have experienced it on newly delivered (not sold) cars as well. They seem to be of the "it's the gas and the computer" school of thought....having even called the state dept of energy to check the local gas composition (this is regulated in MA, and the state supposedly knows the % of ethanol being mixed into gas sold in the Commonwealth ).

I may try to get them to reload 33.2 (it's what's in there now) when I bring it back in a couple of weeks. I have to get my sunroof mechanism replaced (!!) and some other piddling things done. Heck, the performance probably won't get worse...and besides, it was actually BETTER than it is now right after 33.2 was installed about 6 weeks ago.

Yes Phobol, it DOES keep getting worse (in my opinion).

 

I have a MC and now that the summer has kicked in, I get the same exact thing. On a hot day its slow as hell from the start. Lurching and sluggish, I am flooring it just to move. With the A/C on FORGET IT...feels like the car wants to die. Oh well.

 

I made some fake marketing graphics one weekend after badstarts and a few morons with the "Is that a chrysler??"

 

We've got a cold front coming and we're supposed to be at 64 degrees this evening. I bet I still get the stumbles. I'll let you know!

 

>>I have a MC and now that the summer has kicked in, I get the same exact thing. On a hot day its slow as hell from the start. Lurching and sluggish, I am flooring it just to move. With the A/C on FORGET IT...feels like the car wants to die. Oh well.

You live in Sarasota right? Just trying to figure out if it's really the heat.

 

Thought I'd weigh in on this issue. My MCS is a Jan. 2003 build that I picked up in Feb. The only mod I've done so far is a Madness intake. (And to put in Amsoil, which I believe can be counted as a mod - thanks again, Graham). I have the stumble on take-off, but, this seems to go away after driving the car for a few minutes. The car cranks longer on initial start-up than most other cars I've had/have, but, again, this seems to be only on the inital start-up. When the engine has warmed up, it doesn't crank long at all on re-start.

I don't know, given the delivery date of my car, which ECU update I have. If anyone knows, let me know. However, after reading all about this problem here on MCO, I'm very relunctant to try to do anything about it on a visit to the dealer.

 

Jsun-
I have an un-modded MC with no ECU upgrade and have also noticed my low RPM performance getting worse. In yesterday's 90 degree weather, I had to basically floor it in 1st to inch through rush hour traffic.
Now I'm worried that the upgrade may make this problem even worse.

It's funny, because I continually get jackasses wanting to race me off the line, when the reality is I couldn't beat a Greyhound Bus off the line.

 

>>It's funny, because I continually get jackasses wanting to race me off the line, when the reality is I couldn't beat a Greyhound Bus off the line.


Sad, but true!

 

>>Jsun-
>>I have an un-modded MC with no ECU upgrade and have also noticed my low RPM performance getting worse. In yesterday's 90 degree weather, I had to basically floor it in 1st to inch through rush hour traffic.
>>Now I'm worried that the upgrade may make this problem even worse.
>>
>>It's funny, because I continually get jackasses wanting to race me off the line, when the reality is I couldn't beat a Greyhound Bus off the line.

You've got the "bog" problem we all had going into A/C season. Doesn't sound like the stumble problem. Whatever you do, don't go anywhere near a dealership until the next release is available. Some bright tech in the back might routinely give you an upgrade and you'll be just like the rest of us.

 

>>>>I have a MC and now that the summer has kicked in, I get the same exact thing. On a hot day its slow as hell from the start. Lurching and sluggish, I am flooring it just to move. With the A/C on FORGET IT...feels like the car wants to die. Oh well.
>>
>>You live in Sarasota right? Just trying to figure out if it's really the heat.
>>

Graham, Ants lives in NY (Westchester County) and is a MOTORING ADVISOR

BTW, while changing weather (heat) seems to be a factor, I have to note that I didn't have this problem last September when I first got the car. Last September was hotter than hell up here in Boston. So, I definitely think that this is something brought on by the software upgrade. I hate to think about what this is going to be like as the summer wears on and there's no fix.

I guess the up-side (?) is that US MINI dealers south of the arctic circle won't be able to sell any MCSs until a fix is released. I can't imagine taking a test drive in a new MCS and being enthusiastic if it has this problem....as all of the new ones seem to.

 

Been away moving to a new house for a while, and was interested in what I've missed over the last week.

I have about 1000 miles, post 33.2 upgrade, which was done to fix the "cold start problem". I didn't initially notice the stumble, but like you seem to have found out, it has become worse, especially with the warmer weather.

I'm happy to trade some quirks for the positives of this little car, but this is getting worse, almost to the point of being dangerous.

I have an appt next week (in Pittsburgh, 3 hours drive away), I'll see what they will say about it.. Of course, by the tie I get there the engine will not be cold, and I can't stay overnight for them to test it. Arrggh :evil:

 

>>Jsun-
>>I have an un-modded MC with no ECU upgrade and have also noticed my low RPM performance getting worse. In yesterday's 90 degree weather, I had to basically floor it in 1st to inch through rush hour traffic.
>>Now I'm worried that the upgrade may make this problem even worse.
>>
>>It's funny, because I continually get jackasses wanting to race me off the line, when the reality is I couldn't beat a Greyhound Bus off the line.


HAHA exactly. This is the slowest car off the line. Also I dont live in Sarasota I live in NY, but its 98 degrees here for the past three days and my MINI hates it.

 

Ants, what about the new cars on the lot? Have you (or the other dealership folks) seen any negative customer reaction when they test drive an MCS in this 98 degree heat? I'm just thinking as I said above that this boggy performance and stumble must be a killer as far as MCS sales go. How do you MA's explain that?

 

>>1) What's your impression of low end performance?
>>2) Has your car "changed" in terms of performance with the advent of warmer weather?
>>3) Have you had your software upgraded and/or what's your build date?
>>4) Do you notice your air conditioning having a negative impact on power/acceleration?
>>
>>Thanks for the data!
>>

A few comments that might interest you:
I have a bone stock 12/6/02 build 2003 MCS with 16" V-spoke wheels.

1)
I am ok with low end grunt with the exception of my long comments below:
I don't expect that much grunt from a 1.6L blown engine below 3k, and certainly not below 2k. When I want to move, I rev to at least that much before engaging the clutch, but see my text below.

2)
Based in my seat of the pants dyno, yes, the car's performance in city driving has decreased in warm weather. I assume that is because the intercooler gets heat soaked, robbing probably a good 15-20 horses through lack of cooling of charged air. See also AC comments below.

3) I have had no software upgrade and build date was dec 6 2002.

4) YES,
and I have a big beef with that, not so much with the actual power once I rev above 2.5 to 3k, there the AC-induced power loss is within margins acceptable to me. My problem lies in the now almost non-existent throttle response of the drive by wire system with AC on, from idle before engaging clutch! the rpms will take 2-3 SECONDS to come up, and it will take at least that long before you can engage the clutch and move off the line!!!!

here we go:

Yesterday was the first time I got into a really nasty situation with my MCS: it was early in the morning (6 am) and I had not had coffee yet (my only excuse). I had to turn around on a 4 -lane road, and waited for a gap in traffic, not much at that time. Did the U-turn but misjudged (no coffee, ok?) and ended up coming up short on the curb. No problem, trafffic was still a ways away but coming up fast. So, I wanted to reverse a tad and then pull out.
Well, I engaged reverse - and stalled the engine, aaarrrggghhh!!!!!

Luckily thanks to the alertness of the other drivers they noticed me stalled across 1 1/2 lanes and traffic in both lanes stopped to allow me to re-start, back up and pull away. How embarassing! Thanks to the other drivers for being alert this early in the morning!

Why did I stall?

I think for several reasons:
No coffee yet :smile:
really though, I think what happened in part was this:
AC was on, and that does two things: it robs engine power, but it also reduces the rate or speed at which the engine revs up. To move the MCS off the line, you need about 2k rpm or better yet 2.5 to 3k, if you are in a hurry. With the AC OFF, the rpms come up faster than with AC on. Because of the electronic throttle (drive by wire), the rpms come up VERY slow in the first place. IMHO, the MCS has the slowest rpm increase from idle of any car I have ever driven. Add AC, and the intial pre-clutch engagement throttle response is really, really bad. Did I say it is bad? It is abysmal!!!
Once you have the rpm up and engage the clutch you can get off the line ok, but until you get the rpm up 2-3 or more seconds pass!

So, in my great haste yesterday I did my usual response that would have worked ok with AC off: jab the throttle hard - and I have a feeling for how fast the rpms come up without AC - and then drop the clutch to back out, put in 1st, and off I would have been and out of harms way.

Well, I must have dropped the clutch before the rpms had nudged at all because of AC on, and stalled. If the other drivers had not been alert, it would have been a nasty wreck (it is a 4-lane road where some reach 45-50 mph).
So, thanks to the other drivers, and I want to take this moment to point out that while we often rant about inattentive drivers, cell phones etc..., in this case I was the one that caused the trouble, and others were attentive. Thank you others!

Long story, short summary:
I am very wary of the electronic throttle, and do now dislike it more than ever before. The response of the throttle from idle with no gear engaged, and AC on, is disconcertingly slow. I think it is possible for the driver to adjust to that, but in emergency situatio, this may be tricky. In addition, the difference between AC on and off can result in emergency response throttle blips that are either too slow if you are accustomed mostly to how the throtttle works with AC off, too high if you take into account the AC effect, but the auto AC goes off right then.

In my view this is definitely something that MINI should improved, but i don't know how.

M.

 

MG, thanks for the detailed discussion of what I personally think is yet another aspect of this problem...i.e., throttle response (particularly with the AC on).

I'll just add that I've discovered the same effect when I try to drive out of my office parking lot with the AC on. To drive out, I need to drive up a hill that's at about a 40 degree grade (yep, steep). The grade runs for about 50 feet up the driveway onto the main road. This means that you need to hold your car on the hill and then accelerate out of the driveway into a break in the traffic. IT AIN'T EASY...and if you're not careful, you can stall out with about 1/2 of your car into traffic. Yikes! And at any rate, lately in my MINI I end up puttering out into traffic (often with the traction control killing the power) and creating a slowly moving obsticle to drivers in my lane. Point is, this has gotten a lot worse with the warm weather and the AC being on, and is part of the situation that made me start this thread.

My solution is to rev the engine up high (like a High School kid just learning how to drive standard) and then spin out into the lane...and this of course causes the traction control to come on if I haven't turned it off. ARGGGGGHHHHH!!! So, now I turn off the DSC and the AC until I'm well under way on the big road.

Seems kind of stupid to have to drive this way....

 

>>Ants, what about the new cars on the lot? Have you (or the other dealership folks) seen any negative customer reaction when they test drive an MCS in this 98 degree heat? I'm just thinking as I said above that this boggy performance and stumble must be a killer as far as MCS sales go. How do you MA's explain that?


Have not experienced any problems with the test drive cars..

 

>>My solution is to rev the engine up high (like a High School kid just learning how to drive standard) and then spin out into the lane...and this of course causes the traction control to come on if I haven't turned it off. ARGGGGGHHHHH!!! So, now I turn off the DSC and the AC until I'm well under way on the big road.
>>
>>Seems kind of stupid to have to drive this way....

Yep, I do that too now, when I can anticipate it: AC off, and sometimes even DSC off. My problem yesterday was a less anticipated (and stupid) action of mine, so I had not prepared properly by turning AC off.