Cold Start Stutter & hesitation, ocassional cut out [Archive] - MINI Cooper Forum - MINI2 Mini Cooper Forums

: Cold Start Stutter & hesitation, ocassional cut out


paz
Feb 3rd, 2012, 01:04 PM
Hi All,

I've searched, but can't find symptoms which are exactly the same as mine. I've got some ideas but being new to these cars just wanted to see what you all thought.

On cold startup (not just cold weather) the car seems to idle ok, but when you pull off the power will drop completely and the car will stutter and accelerate slowly, sometimes even cutting out all together.

From the reading I've done, I was wondering if this could be the carbon build up problem? On my car, in situations like this I would have changed out the serviceable ignition system elements like plugs, leads, dizzy cap and rotor arm but don't know which bits are best to change on the mini? Also wondered if its worth putting some kind of flush in the fuel to clean out the injectors and any build up etc?

I'd appreciate your help with this, thanks in advance :biggrin:

paz
Feb 3rd, 2012, 04:24 PM
Oh, and its a 2001 mini cooper with 78k on the clock :)

Thanks

element140
Feb 3rd, 2012, 05:58 PM
I too have a 2001 cooper, although it has 76k on the clock, and I have the same issue. I had to replace the battery today, as I still had the original battery which died, and to some extent that has helped. I have changed spark plugs which didn't help. I believe the issue lies with the coil pack. The post for cylinder 3 (I think) is prone to rust and is well documented on this forum. Mine is rusty, but havent yet got round to giving it a proper clean. This would be a good place for you to start

paz
Feb 5th, 2012, 12:42 PM
Ok, just checked the coil pack And all the posts are pretty clean including number 3.

Gave them a clean down anyway with wd40.

Anything else I can check?

Thanks

element140
Feb 10th, 2012, 10:41 AM
Next steps would be the usual, check plugs, leads and check the battery. My battery has just died like I said, but it would stutter regardless of external temperature. The battery gave up due to the cold winter we're having.

marque
Feb 10th, 2012, 10:58 AM
Hi ya
carbon build up problem is really gen 2 engines ,gen 1 engines don't really suffer from this.
Like you say check your plugs and air filter and your intake hoses for splits or leaks to start with.
Do you have access to a diagnostic tool if so see if you have any codes some codes don't bring the EML light on.
Such as the pre cat 02 sensor which could be causing the problem if the heating element or the sensor has failed
As good injector cleaner like bg44k is always worth doing and a sea foam treatment is worth while I do mine twice a year depending on my millage

Hope this helps

fintious maximus
Feb 11th, 2012, 07:15 PM
Hi,mine also does this - where are the coil packs please - assume top of engine round the spark plugs?

msofty
Feb 11th, 2012, 08:10 PM
Might be an obvious question, but what octane are you putting into your Mini - I used to have this problem when I would get low quality fuel (not at least 89+ octane)

fintious maximus
Feb 11th, 2012, 09:50 PM
I use standard unleaded,usually from a BP station..

Soopercooperinfo
Feb 12th, 2012, 12:27 PM
Run a can of BG44K through it and see what happens. My mechanic swears by this product. Good luck.