Cylinder Misfire Count?

[T123456]

Was scrolling through different data on Forscan and noticed it said I had 2 misfires on Cylinder 6 during my last drive cycle (about 15-20 minutes trip). So I decided to take a look the next day to see what it said, 1 misfire on Cylinder 2, and 2 misfires on Cylinder 6 during the same 15-20 minute trip. Is it normal for 1 or 2 during a drive cycle? No check engine lights, no noticeable issues.

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[Cobra Jet]

Try swapping ignition coil from Cyl 6 with one adjacent. Take another ride and data log. Does the misfire still occur on cyl 6 or does it now occur on the adjacent cyl from the coil swap?

 

[ice445]

My experience with Ford misfire counters tells me that's completely normal. <10 events on a typical drive cycle is a non issue. The way it measures it is accurate, but not 100% accurate. Things like cam profile switches or sudden load/throttle state changes can log an event. In fact, the only way to get a check engine light to pop up is to get a few hundred misfires, or to get severe misfires where the power balance is way off and there's essentially no combustion taking place (where the check engine light will flash).

Take this with a grain of salt though, most of my logging experience is from older vehicles. I've never logged my Mustang, and maybe the methodology has improved and you actually should have zero. I doubt it though, combustion is an imperfect process by nature.

 

[T123456]

Try swapping ignition coil from Cyl 6 with one adjacent. Take another ride and data log. Does the misfire still occur on cyl 6 or does it now occur on the adjacent cyl from the coil swap?

Watched over the next few trips and there’s no rhyme or reason. Now it says 1 misfire on cylinder 3. Seems it happens immediately after starting the car and not necessarily while driving.

 

[Basspro302]

Thats normal ignore it.

 

[The_Mad_Patcher]

Watched over the next few trips and there’s no rhyme or reason. Now it says 1 misfire on cylinder 3. Seems it happens immediately after starting the car and not necessarily while driving.

 

[The_Mad_Patcher]

I use Forscan also and get the same small amount of random misfires. I don.t worry about it...but I check regularly to be sure.

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