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Acceptable misfire

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3
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Location
Fountain valley
#1
Hello long time lurker here, over 4 years now finally made an account. I am at 86k Cobb stage 1 Injen intake. I started monitoring knock and misfire count after I put in new spark plugs. A code hasn’t been thrown but I’ll get misfires going to work (less than ten) ~10 miles of driving. Since a code hasn’t been thrown does that mean everything is okay? I thought misfire was a bad thing. Does anybody else get misfires read on ap but not have a code thrown?
 


Messages
288
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320
Location
Beverly Hills
#2
Hello long time lurker here, over 4 years now finally made an account. I am at 86k Cobb stage 1 Injen intake. I started monitoring knock and misfire count after I put in new spark plugs. A code hasn’t been thrown but I’ll get misfires going to work (less than ten) ~10 miles of driving. Since a code hasn’t been thrown does that mean everything is okay? I thought misfire was a bad thing. Does anybody else get misfires read on ap but not have a code thrown?


So this is a very good question. Short answer is probably no. There is an acceptable number of misfires per 1000 rpm. The big thing to watch is ignition correction(ign cor cyl 1-4 on the ap)

This blog post is a big help. I think this company is a little reputable. 🤷🏼*♂️

http://stratifiedauto.com/blog/misfires-and-the-ecoboost-when-should-you-worry/

Also, you can call Cobb and ask them and they are super helpful in explaining some of this in detail too. I always liked hearing things from a couple different sources.


Sent from my iPhone using Tapatalk
 


OP
P
Messages
3
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0
Location
Fountain valley
Thread Starter #3
Thanks, I read that article and I guess if no code is thrown then everything should be okay. As for ignition correction I haven’t seen any negative timing and no knock recorded. If anyone else sees misfires recorded on ap but no code please share.
 


A7xogg

Active member
Messages
580
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143
Location
Hampton roads
#4
You probably have some carbon build up and it misfires slightly till it's warmed up 100% which is why on short trips you notice it
 




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