Stalling and backfiring

[jimster]

Hiya, bad form to make my first post a technical question, but ah well

my fd3s has (today) developed a problem idling, it drops below 750 and has stalled a couple of times, and on a short drive just there, it\'s started backfiring, and the heat lamp flashes constantly....

Only mods are an apexi air intake, and an (untuned as yet) powerfc. Everything else including the exhaust are stock. I\'m running 99RON fuel.

It\'s not an apex seal - i know what that is like , the car seems to be ok power-wise, and this happens at low revs, so don\'t see it being turbo related...

Any ideas would be appreciated.

Cheers,

Jim

[peterwolds]

Welcome 1st post a member & a problem sorry to hear,link below may be of help to you
http://www.mazdarotaryclub.com/forums/showthread.php?t=10342&highlight=heat+lamp+flashes

[gsb876]

Almost certain the sparkies need changing bud, happened to me while stood in a queue car started to backfire then died there and then, already knew what it was got the car home ordered new sparkies and fired up straight away.

If unsure get one of the sparkies out and see how used it is.

[jimster]

Thanks for that Pete. Feel like a bit of a tit for not searching properly :2Confused ...

I\'ll have a looksy at the commander in a bit when i take it out, and i\'ll make a note of the sensor readings as well. My symptoms are different though in that it\'s not even idling consistently at ~800rpm, and the backfire attracts a lot of attention :rollin

Cheers

Jim

[jimster]

Cheers gsb876.
 
Just took it out there. I got round the corner and it completely died. The heat light was between flashing slowly and on constantly. There\'s a strong smell of petrol, which backs up the spark plugs theory - although there are less than 1000 miles on the ones in there... Injector duty never got above 30%
 
I have a stash of plugs, so i\'ll fire another set in there tomorrow and hopefully that\'ll cure it!
 
Thanks
 
Jim

[peterwolds]

dont worry about feeling a ***
Jim what heat range plugs are you running ?

[jimster]

I\'m running 7s and 9s.
I\'m pretty certain they are in the right way , sure, almost sure - i\'m beginning to doubt myself..... :-(

[Mazdarotaryparts]

Hi Jim and welcome to MRC

If you still have your stock ECU bolt the stock one back on and see what you get as I wonder if the PFC has died, rare but it does happen.

 


When it is running if its really erratic you could have a vacuum hose off the Map sensor which is the small square box on the bulkhead behind where the throttle assembly is which will mean that the ECU won\'t know whats going on.

Real difficult though to analise a car this way though.

[jimster]

Just swapped out the ECUs - stock one back in. It\'s now idling and running fine - but then I only drove it for a few minutes. I\'ll take it for a decent spin later and see how it goes....