I need help again!! My car driving me up nuts...
#1
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I have a very random misfire, it's pretty un-repeatable, it occurs 90% of the time during cruise, but can happen at any time.
see the attached pic from a datalog, (I can attach that if anyone wants it?)
![](http://www.asbi52.dsl.pipex.com/miscpics/missfire.png)
you can see that the revs hold steady as does TPS and MAP, but where you can see the AFR fluctuate I have a miss fire, it's almost like the car doesn't fire on one cylinder. It's extremely annoying, especially now my daily commute now involves lots of steady state cruising :-(
I've got a set of Mazdaspeed Ignition leads and tried swopping them for another set with no joy (neither set are new however...) I've also tried new plugs, (NGK-R's and Iridiums) to no avail.
I'l literally at the end of my tether at the moment, long hours and a stressful drive does not make me enjoy my car!
Any and all advice is much appreciated!
see the attached pic from a datalog, (I can attach that if anyone wants it?)
![](http://www.asbi52.dsl.pipex.com/miscpics/missfire.png)
you can see that the revs hold steady as does TPS and MAP, but where you can see the AFR fluctuate I have a miss fire, it's almost like the car doesn't fire on one cylinder. It's extremely annoying, especially now my daily commute now involves lots of steady state cruising :-(
I've got a set of Mazdaspeed Ignition leads and tried swopping them for another set with no joy (neither set are new however...) I've also tried new plugs, (NGK-R's and Iridiums) to no avail.
I'l literally at the end of my tether at the moment, long hours and a stressful drive does not make me enjoy my car!
Any and all advice is much appreciated!
#5
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Attached, thanks Jim,
I tried to use some of the PnP settings to see if it was setup related, that's why my VE and ignition tables don't match!
As an aside when I tried the PnP VE table it was Waaaaay to lean, it barely ran it was that far off - which I don't get at all as it should run right even tho I have much larger injectors, the Req_fuel setting should sort it out?
I tried to use some of the PnP settings to see if it was setup related, that's why my VE and ignition tables don't match!
As an aside when I tried the PnP VE table it was Waaaaay to lean, it barely ran it was that far off - which I don't get at all as it should run right even tho I have much larger injectors, the Req_fuel setting should sort it out?
#8
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I hate to break this to you but try 029t, the non-hr version. I always had hiccups and oddities here and there with the hr as well. If you still have the original injectors, you may want to swap them in for a test and drive along (no boosting obviously). Hope that helps,
Jim
Jim
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hey check this out http://www.rivercityroad.com/garage/jumpingtach.html intermittent ground issue common on 1.8's wich causes misfires and eventual coil failure. It is a free and easy fix that might help.
#10
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I hate to break this to you but try 029t, the non-hr version. I always had hiccups and oddities here and there with the hr as well. If you still have the original injectors, you may want to swap them in for a test and drive along (no boosting obviously). Hope that helps,
Jim
Jim
#11
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![Default](https://www.miataturbo.net/images/icons/icon1.gif)
hey check this out http://www.rivercityroad.com/garage/jumpingtach.html intermittent ground issue common on 1.8's wich causes misfires and eventual coil failure. It is a free and easy fix that might help.
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