I've been doing a refresh of my 2006 R53 JCW and sorting some of the key maintenance points and upgrading where worthwhile.
https://www.northamericanmotoring.co...refresh-7.html

It's been hard work but worth it for all the enjoyment the Mini has given us. But something has started to worry me now. When I first bought the Mini, it wasn't starting up cleanly (needs about 3-5 secs of cranking), from cold or hot, idle was a bit rough and it had a habit of cutting out randomly, while waiting in traffic - its been doing it since the summer when it was very hot (50'C) and still doing it now when its about half the heat.

I initially put this down to just needing to give it a full service. But even after a pretty full service (new plugs, ignition coil, HT leads, oils and filters, just fuel filter still to do), it's still not starting up as it should and still cuts out randomly - the drama always starts with the various dash lights and gauges going crazy and spontaneously flashing on and off, and the needles jumping up and down, engine starts juddering and cuts out - but the engine doesn't always cut out - sometimes just the lights and gauges will play up on their own. It usually happens when I am waiting in traffic, but just once or twice it has happened when I've been driving along at around 40-50 kph.

After I start it back up, a few specific things always change - the AC recirculate button will get cancelled, but AC still carries on- the digital clock goes blank (--:--), the odometer gets zeroed out. But the saved radio stations never get cancelled from the memory. Yesterday was the worst day I can remember for the gauges and lights since buying the car - it must have carried on for a good few minutes, while I was stopped at the signal.

And early this morning, just after a short 2 minute drive, for the first time ever in my ownership, I turned the car off and the power went dead completely. No interior lights anywhere, nothing at all. Tried turning it back on, nothing at all. It felt like the battery had been disconnected . So I checked out the battery and was pulling/twisting on the connectors, both -ve and +ve sides to see if they were tight (which they were) - and as I was fiddling with the +ve side the interior lights came back on - there is a small plastic box attached on the +ve battery cable (?fuse), with a short length (4-5 inches) of thin brown wire coming out the side which seemed very loose at the connectors. Anyway, started it back up and all ok since.

Has anyone experienced anything similar ? Any suggestions most welcome.

We had a lot of rain again 2 days ago - not sure if that's relevant - but the problems have gotten worse more recently since the rains. Just read a thread about water leaking into Body Control Module.

 

 

It may be a long shot. There had been cases previous owner had an accident that triggered the use-once pyrotechnic battery disconnect breaker (a breaker it is) on the +ve terminal post. Instead of replace it as one should, some chose to jimmy the discharged contacts back into position. Evidently this "repair" only lead to intermittent contact at best.