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As the topic suggests, my car has difficulty restarting usually in warmer weather. It started off being fairly intermittent but has been getting worse in the last few weeks. The car drives fine - I haven't had the car stall/die on me while driving like some others have experienced - although most of my recent driving have been short trips of under 40 minutes.

What typically happens is this:
1) Drive for 20-30 minutes so everything is at normal running temp
2) Stop for 10 to 15 minutes - eg property inspections, some quick shopping, etc
3) Get back in the car and it won't start. Other times, it will splutter for about 5-10 seconds then dies. And other times, it will start second go.
4) If it doesn't start, letting the car rest for another 5-10 minutes usually does the trick.

The latest incident was last night:
1) Took a 20-30 minute drive.
2) Stopped into Broadway shopping centre in Sydney for 15 minutes. Last night was not hot in Sydney by any means.
3) Tried to start the car and it spluttered for about 5-10 seconds then died. This happened 3 to 4 times. Luckily I was still parked.
4) Next restart, I held the throttle for about 10 seconds at around 2000rpm. Then left the car to idle. I spluttered for another 10 seconds and died. This happened 2-3 times.
5) Another restart and I held the throttle for about 20-30 seconds at around 2000rpm. Then left it to idle and it idled properly. I drove off and all was good.

I am at a loss and I have already had the fuel filter and some other bits (but not fuel pump, CAS nor coil packs) replaced. So spent about $300 already and the problem hasn't gone away. So hoping someone out there can lead me in the right direction before I spend more money.

Cheers,

Vincent

What \"other bits\" have been replaced?

Is it repeatable?

Try taking it to the mazda dealer, they can run a diagnotic on the ECU (error codes are remembered inth ECU afaik).

To be honest it sounds like coil packs, if it is only happening in warm weather. Although if both your coil packs were playing up you would get 0 spark and it wouldnt start at all...

to test use a spare spark plug and attach it to 1 unplugged lead and watch for spark while someone else cranks...

Have a similar problem with my NA6. Do 4 laps of Phillip Island, stop for 5 mins and then try to restart. Motor turns over fine but does not fire. It will rollstart in about a metre and then run ok. Replaced the plugs when it first happened, but is starting to happen again. Could this be coils breaking down due to heat ??

Grumpy, what about your ignitor? It is on the driver's side fender just next to the stru top. If it is rather hot, it may be on the way out. So with cranking voltage reduced when hot, there may not be enough juice to fire tha coils, that's probably why it starts when you roll.

Grumpy wrote:Have a similar problem with my NA6. Do 4 laps of Phillip Island, stop for 5 mins and then try to restart. Motor turns over fine but does not fire. It will rollstart in about a metre and then run ok. Replaced the plugs when it first happened, but is starting to happen again. Could this be coils breaking down due to heat ??

You would expect it to start to miss or at least lose power towards the end of the sprint if it was coilpacks. But then again, the airflow may be just keeping them cool enough while you're racing and when you're stopped they soak up a bit more heat and fail.

Sounds like the same problem/symptoms Agro was having...CAS sensor or something like that?

It does seem to be the CAS which has now been replaced. See how she goes over the weekend.

Thanks for the help guys. Just did the Natmeet track day and it did not happen to me. The nephew went to move the car, and it did it for him. Took spare coil pack but did not change them over. Might do it before Winton again on the 6th April.