My 2003 MCS JCW - with custom CAI, Lordoftheflies dampener & screamin demon/livewire ignition - stumbles and lurches at launch like a drunken sailor. This is nothing new with the older Mini's and I'll just have to live with it for the most part, I know. That said, what other modifications can I make to lessen this stumble and lurch? Some of them I'm considering are (in no particular order):
- New tire/wheel combo - right now I've got the heavyweight Momo GT's and runflats
- DT BVP
- VGS (maybe)
- Lighter crank pulley

Which one of those mods would help the most? Any other ideas?

 

I believe the DT BVP will help with the stumbling. I have that, and I like it that it works. Downside is that fuel economy will decrease very slightly.

 

If it feels like the power cuts out just as you reach the last bit of the clutch engagement, then go to the dealer and get updated software. Should cost you .5 to 1 hour max if you are out of waranty.

 

I have an 03 MCS, Stumble was terrible when new. After JCW install, TSW damper, and DT bypass valve, stumble was resolved, now it's just ssssssmooth!

 

002, Yes, that's exactly the symptom. Right at the last bit of clutch engagement it stumbles and almost dies unless I have the rpms at at least 2K -2.5K, then if I'm lucky it wont stumble.

I did go to the dealer and they said the software was current and once they drove it said it was normal. I definitely got some attitude with the question though. Is it possible that they didn't even check? Can I check the software version? What's the current version?

 

Well after driving in the hot day, 103f today, I really notice the stumble and lurch. It gets far worse the hotter it gets.

The power literally cuts to near zip on the last bit of clutch unless I'm feathering the clutch at 2800 rpm or higher. Even then sometimes it cuts. I also noticed that even if I go WOT while letting the clutch out the power cuts unless at 2800 or higher. DCS is turned off, AC is on Auto and set at 74f. I'm not trying to launch like a rocket or granny go, just normal traffic take off.

I've driven manual for 20 years and never experienced this.

Is this normal? Anyone got any ideas?

 

That sounds just like the programming issue, but you would have noticed this since getting the car. Did you buy the car new and are just now experiencing this or is the car new to you?. I don't think that they can tell the SW version, especially if it was done a while back. Did they tell you what version it had (to back up the story)?

 

002, I just bought the car used about 5 weeks ago. It had 12K miles on it when I got it. It's done this since I bought it. The dealer didn't tell me what software version and said that the behavior is normal. I'm thinking I need to take it back in again.

On this thread https://www.northamericanmotoring.co...ftware+version it looks like figuring out the software version is tricky at best.

 

With that low of mileage, I doubt that it has already been programmed for this issue.

If it is under warranty and is a 10/2003 or ealier prodction, then take it back in and politely ask them to check "service information bulletin 12 02 03"
and reprogram the effing car.

If it is not under warranty you will have to pay for it. You should be charged .5 to 1 hours labor max. It is easy and quick to do, 15 to 30 minutes. If you pay for it, have them print out a copy of the "final report" when programming.

Before going postal, give the service advisor a chance. This issue is a few years old an may not be on the advisor's mind (if they have even worked there that long). Be fair but stand your ground. You are not crazy and can probably drive a clutch just fine.

Back in 2003
My girlfriend and I had msc's that were 1 month apart and both had this issue. I was also working at the dealer (not as a tech though). I had been asking a tech/friend to let me know as soon as a fix was available. The day came and I got the word, there were so many pissed customers that they sent over an early german version to load onto the cars. I asked my advisor to write up the ticket and he proceeded to "tell" me that there was NO fix, because there was NO problem. A few choice words and 20 minutes later, the stumble ws gone forever.

The moral of the story, SA's rarely know what they are talking about and they don't even believe people that are "in the know". Don't take it personally.

 

19% pulley, the quick and easy fix to ANY low end problems! :P

 

It is not a low end problem. The power literally cuts out, similar to how asc feels.

 

Does it do this when you have the a/c off? If it's set at 74 and it was 103 i'm sure the a/c was probably on. My car run's like crud when the a/c is on. It was 98 here today, and it was off!!

 

002, Yeah, it's just like ASC/DCS, but worse. It almost stalls at lease ASC/DCS seem somewhat controlled even if really annoying:-)

Jiminni, The only time I'm able to feather the clutch and throttle with out a stumble or lurch is when it's below 80 outside and the AC is completely off. The AC is definitely a hog, I get that.

One more symptom that might be related, when in idle for a couple of minutes, the engine goes into the really bizzare cyclical low idle, almost like a stall. Sometimes it will pull out of it, sometimes I have to blip the throttle to get it out of the cycle.

 

Sounds like its had bad gas in its life.

Perhaps it sat with gas for too long, and it started going bad.
Perhaps the previous owner wasnt using the 91/93 recommended octane.

After getting your "flash" from the dealer, try running a couple of tanks of Chevron Techron Fuel system cleaner. It's really helped on EVERY car I've ever put it in, and thats about 10+ now.

 

I also get the low idle every now and then. A blip or two of the throttle usually fixes it. Back in '02 there were some major cold start/bad idle problems that were fixed with SW updates.

 

Interesting on the fuel. So potentiall carbon deposits from improper detonation could cause this? I did run a fuel system cleaner through it when I got it.

 

The best starting point is the software, especially if it is free. I bumped to v38 from v34 on my 2004 (10/2003 build date) and the change was dramatic. Decreased the occurrence of the lurch and moved it to the decel side vs. acceleration side.

Later I bumped to the Dinan basic software upgrade and that all but removed the lurch & stumble (and gave better performance all around).

I recently added the DT BPV and I don't think it really did much for the remnants of the lurch but you can notice the quick response on boost.

A pulley will not guarantee any reduction of stumble or lurch, may even worsen the symptom in some cases.

The seasonal change in fuel additives does make my car burp occassionally, but nothing a quick blip of the throttle won't cure.

Mileage may vary, but there's my experience after 50K miles of fun.

 

Well, I'm at the dealer right now and they state that there isn't a service bulletin with the number 12 02 03. Additionally they claim that with JCW programing, I can't change the ECU programing that this change obviates the stock S programing. Does any of this ring true?

They are also claiming that this could be a slipping clutch, which doesn't make sense at all with only 15K miles on the car.

Any ideas gang?

 

[quote=IncredibleHulk;1518804]Well, I'm at the dealer right now and they state that there isn't a service bulletin with the number 12 02 03. Additionally they claim that with JCW programing, I can't change the ECU programing that this change obviates the stock S programing. Does any of this ring true?

They are also claiming that this could be a slipping clutch, which doesn't make sense at all with only 15K miles on the car.

Any ideas gang?]

The bulletin has been up since early 2003 and was still there about six months ago. It should not have been removed. JCW is included in this bulletin. I am looking at a copy of it right now BTW.

Did the SA tell you this right of the bat or did it feel like a tech looked up the bulletin first? I can call a friend next week and confirm, but it is very unlikey that the bulletin was removed, especially because it cures the problem. I don't think that it is a coincidence that every time I describe a symptom you say exaclty.

PM me if you would like more information about the bulletin or to help diagnose your issue, if is infact not the programming. It is much easier to get to the bottm of something over the phone.

 

002,
Wow, you've got to be kidding!? You've got it in front of you? They looked up the numbers "12 02 03" and couldn't find a related bulletin.

What's frustrating is that the stumble/lurch doesn't seem to happen in cooler weather, say below 80 degrees, so we can't repeat it at the dealership. They are looking at me like and treating me like I'm a crazy person. When I've almost wrecked 3 times now becasue this thing almost stalls on launch in the heat.

Yes, I'll PM you and maybe you can fax it to me or something.

Thanks

 

I don't know if this makes sense but I get this stauling/stumble when there are more than 2 people in the car. It seems like I have to push on the throttle and bring the rmp around 3k for it to lunch. This of course also happens with the AC on on hot days.

 

What I am describing is not when "launching" or trying to move fast. This is just normal trying to get moving with your grandmother as a passenger on sunday afternoon type driving. Basically, you look like you have never driven a clutch before. No matter what you try or how much rpm you throw at it, it wil shut off for a second.

These cars just aren't going to launch quickly at lower prms. They are 1.6l with low compression and a supercharger to drive. That doesn't add up to strong off idle launch.

There is one easy way to figure out if it is the programming issue I described. Do you have a 10/2003 or earlier car that has not had updated software in that past two years or so? I am concerned that people are now confusing normal small engine characteristics for an issue, when really they want to drive a 3.5 liter car.

 

I also just meant normal driving, not bulleting off. Mine seems to be doing that sometimes as well in situations I mentioned above.

 

Well, over time I have "fixed" the stumble -cold start issue, I thought. a couple of ways. UselessChip helped for a month until the ECU learned all of its tricks, then it satrted throwing a bunch of codes and both came back. Removed UselessChip and it ran better, but not gone

Then the bypass went south and dealer replaced it. Ran great for 20k and started again. Dealer offers to change it again. I decide to use DT valve from Waylon and do it myself. Runs better that ever then slowly starts to come back.

Realize that I have 25k on last set of plugs and change them and the oil (5k) at the same time as I reset the ECU(last Sat AM). I had never done that so it had lots of garbage data from the UseLessChip left in there as well as who knows what from the dealer.

Reselts were surprising. Runs stronger than ever. cold start is 90% gone and so is the stumble unless I am dead on 3100rpm for a period of time. Strange thing is it will sometimes throw a "rich" code if that happens.

Will keep trying but unless you have a flash you paid for, try resetting the ECU and drive the 1st few days as "spiritedly" as you safely can and post your results in a week or two

 

I have a 2002 MCS and have the same issue. During the MOTD I was going to get GIAC flash but with the issues with connectivity (no phones and GIAC server was down)we never got the file back. One interesting thing came out of it was that I have some strange fix flash on my car that Helix hasn't seen before.

I just got my car in September with 21K miles and looking at the records it was only at the dealer twice. I should have my car flashed my end of the week and will let you know if GIAC resolves the issue.