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My engine has just stopped when stopping , it's done it 3 times , I slow down to stop using the gears , go onto the brakes to come a full stop and the engine just keeps slowing down and stops , no fuss no drama , just ' I'm taking a smoko' stops.

It's not a drama now I'm aware of it as I keep an eye on the tacho when I'm slowing down but it's not a desireable trait , the plugs and the idle are fine and in every other respect the engine runs very well.

Anyone know what might be causing this ?

Basho wrote:My engine has just stopped when stopping , it's done it 3 times , I slow down to stop using the gears , go onto the brakes to come a full stop and the engine just keeps slowing down and stops.............the plugs and the idle are fine and in every other respect the engine runs very well.

If it won't idle from higher RPM then there is a problem with the idle. Have you recently disconnected the battery or messed around with any engine settings? The base idle speed may need adjusting (http://www.miata.net/garage/ignition.html#idle) or the ISC may have died. (http://www.miata.net/garage/isc.html)

Thanks for that , I adjusted the idle speed a little while ago --completely forgot ---I'll re-set it, I obviously didn't get it right.

The only time the car dos the 'I'm outa here' stunt is in the exact stopping conditions I described otherwise it runs like a champion

Check timing

Gummy ICV?
Timing is unlikely to have moved ten degrees.

TPS working?

Stock car right?

Dann

Does it idle fine?

NitroDann wrote:Gummy ICV?
Timing is unlikely to have moved ten degrees.
TPS working?
Stock car right?
Dann

Thanks for the reply Dan.

I just cleaned the PCV valve , it was gummy but not stuck and seemed free-ish , after a good hit of contact cleaner you can bet it's as free as Mr Humphries now.

I've also cleaned out the throttle body which was suprisingly clean anyway, the butterfy has no sticky points.

I haven't touched timing atall.

Absolutely stock car--even down to new Mazda air/petrol/oil filters

I don't know how to check the TPS but the only time it drops out is under exactly the slowing sequence I've described, and this is at normal trafrfic speeds not belting along to stop-which it does fine.

Okibi wrote:Does it idle fine?

Cold/hot start and run fine, idle fine hot or cold . slow to warm up but I'm guessing that may just be the car type, doesn't affect running.

Basho wrote:I adjusted the idle speed a little while ago --completely forgot ---I'll re-set it, I obviously didn't get it right

Did you do this with the TEN and GND terminals in the diagnostic box shorted?

JBT wrote:

Basho wrote:I adjusted the idle speed a little while ago --completely forgot ---I'll re-set it, I obviously didn't get it right

Did you do this with the TEN and GND terminals in the diagnostic box shorted?

Yep , but I've just done it again and this time I've reset the timing at the same time , it's running fine , I couldn't make it fade out so this might have fixed it.

When I put the timing light on it the read was all over the place then settled to a flakey 10, I reset it to the first marker over the ten hard which I'm thinking is either 11 or twelve, whatever, it runs well at that setting and then I reset the rpm needle to a clear bees under the 1K rpm marker which in my logic would equate to 800-850 rpm.

My guess is that maybe the people who just installed the timing belt , pulleys and all that stuff didn't reset the timing. I just checked and it's not on the job sheet.

Then I found I needed

Basho wrote:I've also cleaned out the throttle body which was suprisingly clean anyway, the butterfy has no sticky points.

Good to hear it sounds like it's sorted. Some forumites have found the TB immediately behind the idle screw gets a bit gunked up & eventually casues idle problems - worth a clean if you can remove the idle screw easily.

The mechanic will never reset ignition timing when they do the timing belt.

Dann