Intermittent fault/garage recommendation

[burns76]

My MCS has developed an intermittent fault over the last couple of days. From time to time when I brake to a stop, as the speed falls to around 10/15mph the engine seems to almost stall and then pick itself back up again. This also seems to affect the brakes and they become less effective for the few seconds that the engine is struggling. I should add that at this stage I'm in neutral so it's not that I've left it in too high a gear (I have a very bad habit of taking it out of gear as I'm braking).

Does anyone have any idea what the problem might be, or how I would go about rectifying it? Also, if anyone could recommend an independent garage in the North West that deals with the Mini that would be great, as I'm reluctant to take it to BMW as they will charge me a fortune to tell me that they've been unable to replicate the fault! I've tried Minisport in Padiham but they were unable to recommend anyone.

Thanks to anyone who may be able to help.

[gonzales]

Can't help with the fault described, sorry. But have had experience with intermittent faults on my MCS, the problem with taking it to a garage is that it never 'performs' when you need it too. The only thing I can recommend is find a decent garage and leave it with them for a few days so they can test it out. Thankfully mine was under warranty and I left it with Williams for them to do this.

I hope you get it sorted.

[tiger333888]

hi mate, sorry about the problem. It could be a faulty air-mass sensor so at a particular rpm the engine is not being fed the right mixture of fuel and air = hence stalling sensation, and during that time when it does stall, the electrics go momentarily hence the failure of the servo brakes...

this is the best guess I have. mention this to the garage and see what they think.

tiger

[burns76]

Thanks for that! I think that given the intermittent nature of the fault (and the fact that it's only just started) I will monitor it over the next few days and keep a record of exactly when it does it, the conditions at the time, etc, and then any subsequent garage visit may be more worthwhile. Unfortunately my P&J is no longer under warranty as it's a 53 reg, so I may need to save some pennies pending the trip to the car clinic!

[tiger333888]

good plan and good luck with the fix. the air mass sensor may require a simple clean to fix the problem - will be cheap fix. Quite common issue on porsches. I had a boxster, and many owners reported their cars not idling consistently - revs would go up and down - not settle - was down to the air mass sensor playing up. May be worthwhile monitoring your car's rev counter while idling - in different conditions- this may give some clues.

best of luck, again.