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What's normal for misfires and knocks?

maestromaestro

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#1
I have been keeping an eye on the data that AP provides on the misfires and knocks. My numbers - over more or less regular commutes, mostly highway, about 40 miles each way, averaging 60 mph - bounce around 9-15 for the misfires and 1-2 for the knocks. Is this typical? Reasonable? And if not, what would these point to?
 


OP
maestromaestro

maestromaestro

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Thread Starter #3
I will start monitoring mine for comparison.

What fuel are you using? Top tier 91 octane or above? How old are the plugs?
I use 93 (it IS Texas, after all). Sparks are quite new, maybe a couple of thousand miles. I have 1 step colder NGKs "custom gapped" by @whoosh.
 


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maestromaestro

maestromaestro

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Thread Starter #5
AP has one that I think is called Knock count or smth like that
 


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maestromaestro

maestromaestro

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Thread Starter #6
I believe that there are individual gauges for knocks on each cylinder. I need to RTFM, dammit.
 


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#7
Just monitor ign corr cyl 1,2,3,4. Knock sensors are very sensitive and give false knock feedback.
 


green_henry

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#8
I believe that there are individual gauges for knocks on each cylinder. I need to RTFM, dammit.
I turned on the Knock Detection and Misfire gauges. I commute 15 miles each way, mostly freeway.

Morning: 0 knocks, 4 misfires
Evening: 0 knocks, 6 misfires

In the evening 3 of the 6 misfires occurred before I even got out of the parking lot.

I run E30 on a fairly regular basis, including today, so I would have been really surprised to see any knocks. As far as the misfires go, my plugs are only a few months old, standard temp. If my commute were 40 miles like yours, I think I'd probably have the same number of misfires, so I'm guessing (hoping?) that's not unusual.
 


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maestromaestro

maestromaestro

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Thread Starter #9
I will look into individual cylinder values. Cobb has some tech info on the ignition timing and learning.
 


FiestaSTdude

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#10
IMG_20220610_145753821.jpg
Do y'all think this is too many misfires for a 20 mile drive on mostly highway? I was monitoring misfires because I have some other issues rn.
 


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#11
idk about misfires, but I never get more than 1 knock event. I monitor on the 3rd cylinder. I think I've read somewhere that the 3rd one is more likely to knock. It happens early in the drive (first 10min?) but never again until the engine is cold.
 




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