Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post - Apparent rich misfire

504 · 11-12-2020, 03:51 AM

Hi all,

Appreciate any guidance in advance

I've recently developed a highly rich condition with stft sitting at -29.9 at idle with12afr (commanded at 15), I'm beginning to suspect that a ignition coil has failed but not sure how to diagnose this with certainty

For context, it's a ecutek tuned turbo 86, been running great for 4 years, no hardware or software changes to note of late. I am alittle Sus about potential disabling of DTC code so can't check for misfire dtc to confirm, or atleast nothing is popping up when I scan for it

Confident I do not have exhaust or intake leaks which tend to produce positive fuel trims anyways. I was thinking it may be o² sensor? But it appears to be reading a corresponding voltage to the measured afr, seems like the less likely culprit

What do you guys think?

11-12-2020, 03:51 AM	#1
504 Senior Member Join Date: Feb 2013 Drives: 2014 86 GTS Location: Sydney, Australia Posts: 168 Thanks: 131 Thanked 85 Times in 57 Posts Mentioned: 4 Post(s) Tagged: 0 Thread(s)	Apparent rich misfire - help Hi all, Appreciate any guidance in advance I've recently developed a highly rich condition with stft sitting at -29.9 at idle with12afr (commanded at 15), I'm beginning to suspect that a ignition coil has failed but not sure how to diagnose this with certainty For context, it's a ecutek tuned turbo 86, been running great for 4 years, no hardware or software changes to note of late. I am alittle Sus about potential disabling of DTC code so can't check for misfire dtc to confirm, or atleast nothing is popping up when I scan for it Confident I do not have exhaust or intake leaks which tend to produce positive fuel trims anyways. I was thinking it may be o² sensor? But it appears to be reading a corresponding voltage to the measured afr, seems like the less likely culprit What do you guys think?