All those with a r53,

I am not sure if some of you guys/girls are aware of the idle troubles that some r53's 50s etc suffer from... It usually begins when you stop at a set of lights then the car decides it wants to stall and you find the ecu kicking in to adjust things in order to keep it running.. Goes from 550 up to 900rpm with a constant up/down motion.. A tap of the throttle sorts this.

There is a lot of asks on the forums but after years no conclusive resolution seems to have been found, i have fixed the issue a couple of times myself on different minis but without a conclusive 'this is the fix' . I believe there is a definite single cause as the symptoms are so much the same when reported by individuals, would love to know if anyone has anything to add to this from personal experience? Remedys/fix/accounts etc

 

My R53 does this after a few minutes of spirited driving. I've checked everything and scoured the DME for anything unusual with regards to adaptations and fuel trims.
My gut feeling is that it's a software flaw.

 

if theres no cel youre fine for now.

could be an o2 sensor on it way out, map sensor, any part of the evap system, boost leak, dirty spark plugs, dirty air filter... just about anything really.

good news is, no cel... probly not a big deal. check routine things as listed above and go from there.

 

Yeah spirited driving definitely brings it on... I find a bad bit of gear change also brings up the symptoms..

In the past I have done all the usual checks as mentioned but like I say... No conclusive fix but I believe there must be 1. Dirty components would introduce a variation of the issue but I have had 2 minis side by side with the exact same idle response so I am more lead to believe it being a failing component or ECU issue.. Maybe not software in general as the problem itself develops as oppose to being there from the word go... But could be static or a ecu malfunction?

I guess I will have to put in more work to finally conclude on this

 

I have this problem too for a long time. I much rather have a CEl to pinpoint the trouble and fix it from there.

 

Since it does not effect the relilibility, driveability, or anything other than folks OCD tendencies where they worry about their cars and what is broken....why stress it.....if YOUR car does this...tap the pedal as stated.... And go on with your life.....
As stated above, it us likely a software issue with the car getting into a feedback loop of some type ...just like the yo-yo...
Buy have never had either...even with a custom tune....

 

Yes thanks for the heads up zippy but we all know it has no effect on nominal running of the car etc etc etc this thread is to share examples and see if anyone has an ultimate fix yet.. Its been discussed for years now and its an intriguing example for any enthusiast and good for those it bugs if a fix ever reveals itself.

 

If I recall right....(going way back...and don't feel like search threads from 2005-06)....
A couple folks found that the fuel pressure regulator (on the fuel rail next to the micofilter) was the solution for some....this part gets baked....and the fact the vacume line that plugs into it can degrade can make things worse...
But part of owning a USED car with a bit of character.... If it costs $$ to fix and it just to say...OK...does not annoy oneself...guess you could try it...but as these cars age...there might be other reasons causing it....let's face it...10+ year old electronics on a English car......do you really want to go down another rabbit hole.....
Either way, good luck!!

 

This is the thing... I have time and money to burn so will give that a try on a car tomorrow.. I'd forgotten about that issue

 

I had this issue with my 2004 and it was really bad from the time I got the car new in 03. MINI flashed my car with the JCW flash and later upgraded my car to a JCW package after finding the software fix worked. I just bought a new 2004 MC40 w 24k on the clock. I am soooo hoping not to have this issue again.

 

I picked up an MC40 JCW with 19K on the clock about 3 years ago and I have had the idle gremlin since the beginning. Its kind of frustrating in the autox grid/starting line. People look at me like, "WTF is wrong with your car?"

Then she whines and we are all good.

 

Haha ,

Ok I changed the fuel pressure regulator on a cooper s late 04 model,

It has not alleviated the issue, same diesel like yo-yoing but only does it for a couple of seconds as oppose to 6-10 seconds, gave it a thorough testing,

So to conclude maybe it is to do with the pressure regulator and something else?? Maybe also changing the clogged fuel filter will do the trick?? The entire thing could all just be fuel related.... Will give it a go this weekend,

If anyone has any other suggestions let me know as happy to investigate them,

 

@ Chili head - Does your MC40 JCW have the MINI "Sound kit" with your JCW package ( 380 injectors ? ) My 03' had this issue for long time until 380's were added about 90K miles ago and flashed DME with JCW software for injector pulse.

 

My car does this every now and then also. When I come to a light and let the motor idle.....I can feel it start to idle rough, and the boost/vac gauge will start to drop vacuum....and the rpms will start to drop. It will sit there for a few seconds and shutter and idle rough, and then it will finally start to build rpm and vacuum...and everything goes back to normal.

Sometimes it will have a few times a week....sometimes it will go for a few months without it happening.

I would be interested to hear if people who have custom tunes still have this issues.....or is it just people with factory tuned cars.

 

No even those with a completely untouched cooper s have approached me with this issue, if there is anything I am sure of when it comes to this issue its that unmodified or modified... It happens to both

 

Tuned or untuned that is from a ecu and mechanical point of view

 

Also if anyone is willing to try this who has the problem...

Hold the throttle at about 775 and 800 and 850 then see if it can hold the revs properly or if it gives an up - down motion

 

When my car starts doing it, I can press the gas a little bit to rev the motor....and it will hold rpm's just fine.

 

I have a RWM tune. I always thought my Mini was just doing a "Harley" imitation. A light touch on the throttle clears the rough idle and that's that.

Its not a frequent issue, as stated earlier, once a week or once every two weeks/ month. As long as it doesn't develop into a stalling issue, I can definitely live with it.

 

Can you elaborate.

 

Ecu maps, s pulley changes... Stock or modified this issue can occur.. May also need to elaborate on the thread for people watching/posting.. Any of us experiencing this already know about blipping the throttle and that the issue does not have any bearing on reliability of the car, this thread is for those wishing to sort it and those intrigued to find a cause and for anyone with info to share, Thanks

 

Over the years, we've read many posts of people stating that a tune fixed this. I had this "issue" for a while, don't ask me how, but now I can't remember the last time I've had it. Maybe it's the JCW injectors or the BPV that helped, maybe it's maybeline. Engine wise, I only have a 15% pulley, 380cc injectors, a DDM Works intake and Detroit Tuned BPV, no tune yet.

 

I have the 200HP kit. No injectors, but not just the sound kit. I did not get the 380's nor the intake.

Just the head, upgraded (coated) S/C, pulley, exhaust, and 200HP tune.

 

Also have this issue from time to time on my '04 with 15% pulley, intake,header/exhaust, JCW 380's and the JCW tune for the injectors. Car is just over 90K. Going to replace the fuel filter in the near future but don't hold out much hope that this will "fix" this issue.

 

I put a new fuel filter in my car, and it didn't fix the random rough idle issue.