Want to know if anyone has dealt with this.
In reading previous post' seems like the stumble was on starting from a dead stop.
My stumble is another variety. Mine occurs under load. Lets say you are doing 40-45, and coming on an entrance ramp. If I stay in the gear I'm already in, and then really put my foot into it to merge, it stumbles, sometimes pretty badly. If I gear down, I don't notice a stumble. So it only appears to happen under load.
On a trip to the dealer, they 'cleaned' the contacts. (Tech didn't say what contacts) I'm thinking it was the contacts going into the coil. Especially #3 plug. (as reported by the tech). After cleaning it was better, but I feel it going back.
Anyone else experience this? I'm looking at buying an after market coil, specificaly this one:
http://new.minimania.com/web/Item/NME3021/InvDetail.cfm
Don't want to spend money I don't need to. Think this will solve problem?
I have a 2005, S with 70k. 15% pulley, CAI are the only mods.

Thanks for any insight or suggestions.

 

can you be more specific with exactly what your car is doing??? I dont know if you read my posts about my "stumble" (I call it a hesitation) but I'll tell you again. It happens in any gear, at any operating temperature, only at a throttle position past 50% and only between 1000 and 3000 rpms. I've changed my BPV to a detroit tuned version and I also changed my map sensor (the one in the intake manifold) with no luck on either part. I was thinking it may be a coil as well but if the coil was bad the car would stumble all the time no? It wouldn't be sooo specific as my car is. Once the car climbs past 3000-3500 rpms it clears out completely and pulls as hard as normal. Also when heel-toe downshifting the engine seems as though it does not want to rev as easily as it did before. Its almost like its getting cut off and will only rev about 500 rpms with a quick blip of the throttle. Where as before I could do a quick blip and it would rev 1500 to 1700 rpms and downshift nice and smoothly. I can't seem to figure out what is wrong and the dealer won't touch it cuz it has a pulley, cai, and catch can on it. The car is still under warranty but they claim they "can't get any good readings from the sensors" which is total BS!! They just dont want to work on my car..........a'holes!!!

So do you have similar symptoms to me?? I'm very curious because it would be nice to have similar people to compare problems to and maybe together we can come up with a solution because these lame *** dealers aren't interested in helping us

Look forward to your reply,
Steve

 

STOCK COIL IS STILL THE BEST ONE OUT THERE

 

maybe new spark plugs or the DT BPV would help a whole lot

 

if you turn off the traction control does it still do it?

 

I am going to start watching when it occurs in regard to the tach. I noticed it last night between 1000 and 3000 RPM. But I can only get it to do it under load. Staying in 5th and then punching it, you feel it 'missing'.
Reason I mentioned the coil is because I took it in once and the dealer's tech said he cleaned the #3 contact (after checking all of them) and that seemed it help it, but it's back. He did show me how the contact was getting dirty, or black with what looks like carbon. Now is it the coil, I don't know. It just that it's back.
I have no problem with normal driving. Going up through the gears in a smooth fashion. It's only when I'm already at speed, and then have to punch it to pass someone, or merge and didn't downshift.

So any thoughts anyone? I have been looking at the coil since that's my only clue, but I'm clueless at this point.

 

Have new plugs in and still does it.
Thanks for some input.

 

Hmmm, will try it. Cna't hurt.

Thanks,

 

The #3 terminal on the coil corrodes on most of these cars - mine does also - just need to check and clean it periodically, and use plenty of dielectric grease.

 

Yeah same here...only under load (maybe I forgot to say that) but if I'm doing 25 mph in 3rd gear and want to pass someone quickly its not happening....gotta go down to second and get the rpms up past 3500 to get it to go. This applies to any gear I'm in as long as the rpms are between 1000 and 3000, just falls completely flat on its face. But same as you, if I accelerate slowly and smoothly it will go nice and smooth, but as soon as the throttle goes past 50% and I really start to hear the supercharger "whine" thats when the hesitation starts. Sounds like we got the same problem man, keep us posted with what you find.

Steve

 

... which is the same symptom I was having before I swapped my header back to OEM - and it's still maybe doing it a little, though not all the time and less severely now...

 

Took your header off blimey? Why?

 

Broken flex joint. Jan's fixing it and I'll put it back on.

 

since I'm still running with the stock header maybe a little reverse psychology is in order with my car. Pick up a header and slap that on and maybe my hesitation will go away Who knows....after all this IS a German made car, things aren't supposed to make sense

Steve

 

Still looking for any input. yesterday it seemed to be getting worse. Guess I will look at 'cleaning' the contacts myself and see if that helps. Can't hurt?

 

I clean (with steel wool) and re-grease (with dielectric grease) the contacts on the coil every few months now, and my misfire/stumble problems haven't come back. I also check the terminals on the plugs, and add a dab of grease to those as well.

 

Thanks, will try that.

 

Would getting a new coil work also? Wonder how long an original lasts?

Thanks,

 

i had gone to a screamin' demon and went back to stock shortly after. the demon gave it up quick . car would just break up bad if i got on it with a load on it . it was pretty obviously spark . if it surges and has on and off power in surges it isnt the coil imo . but if it just goes to crap with really fast stumbling i'd say coil .

 

Check the basics; pick up a cheap Ohmmeter and test the resistance on your wires, or just replace them. Do dry/wet compression tests, check fuel pressure. In my experience these things are pretty good about throwing codes for sensor/electrical issues. Start with the mechanicals first, the electrics can't work correctly if the engine has some internal issue. Check the cat to see if its plugged or breaking up.

 

Thanks

 

I have the same problem, but it's not all the time. When under throttle the engine seems to break up, as if it just stopped firing, then continues. It's a split second at a time, but manages to really disrupt the acceleration.

Some days it doesn't do it at all. One day it was bad enough for the CE light to come on and I thought I was going to have to get it towed. Luckily the Mini kept on going and the CE light went away while I was driving the following day.

I checked my #3 coil and it's a mess, going to order a replacement along with new plugs and wires. 190k miles and all original.

 

My #3 line is also the culprit. Wonder why always #3 I only have 73k on the car. So not sure if I should get a new coil or not.

 

I have a 2006 normally aspirated Mini, and when I start it up for the first time in the day, the car revs surge from 1000 to 1200, waving back and forth, until the car warms up. then when I drive, it has a hesitation that feels either electrical, or like a fuel issue, but no check engine light or anything. It feels as if the power band is non existent, and the RPM's climb, but the car doesn't pull. It only has 30K and is completely stock, and a 5 speed.
Anyone seen this??

 

I have a really bad hesitation when I accelerate, but only when the temp outside is hotter than 70 degrees. Does anyone have advice on this issue?