--- In mazdamx3ownersuk@..., "monsoonmarty"
<monsoonmarty@y...> wrote:
>
> Hi folks, anyone any pointers as to what is causing this? A couple
of
> days ago the idle speed started fluctuating between 750 and 400 rpm,
> now cutting out all together! want to see if I can fix it myself
> before having to part with my drinking vouchers. Any help would be
> appreciated... Cheers
>

One possibility is a vacuum leak, whereby unmetered air gets to the
throttle body - the mixture is too weak and you know the rest. Look
very carefully at the corrugated rubber hose (about 2" diameter)
between the airbox and the throttle body. If there is any crack
(even the slightest) it could be the cause. You can tape it up as a
temporary measure, but a new one is over £60.

It just happens that I have a new one I am thinking of selling on
EBay.

But it could be something else - the "igniter" transistor in the
distributor is a weakness, usually in pre '94 cars.