25 minute Live (Jscan) Misfire Readings.. Opinion

[56cbr600rr]

First time I've used this for more than a few minutes...

The readings here are about 4 miles city and 9 miles highway.. 22 minutes of drive time.. Cylinder three is the anamoly... Cylinder three rang up 17 misfires instantly and early in the drive however when I got rpm's up to pass a car... probaby about 4,000rpm...

I'll do the same reading on my way home and post/see how it compares..

Gladiator 3.6 Sport. Auto. Only 6 weeks old and 1300 miles on it.

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[56cbr600rr]

25 minutes of drive time tonight probably around 12 miles, all city driving. No CEL light. RPMs up to about 4000 several times.

 

[56cbr600rr]

Last time I'm gonna monitor this unless it's needed.

Drive into work this morning. Drove 24 minutes and about 14 miles. 45ish degrees I'm guessing outside.. Start up is included in this 24 minutes. 9 miles on the interstate.

IF anyone is familiar with the JT/JL misfire, just curious if all this is inline and considered "okay" or "normal"?

 

[OHJeeper]

I think you'll see from other posts on this topic, these numbers are normal. People with the cam issues and CEL's are getting in the 200-300+ range over a 20-30 minute period.

You will get more misfires on idle/start, by the way. Just the nature of petrol engines.

 

[56cbr600rr]

I think you'll see from other posts on this topic, these numbers are normal. People with the cam issues and CEL's are getting in the 200-300+ range over a 20-30 minute period.

You will get more misfires on idle/start, by the way. Just the nature of petrol engines.

Thank you for confirming. And kind of what I was thinking as well.

I am thinking about trying a different spark plug in cylinder 3 as it can't hurt and pretty easy to access. Also, unless it's just not reading, I really don't show any misfires at start up.

 

[Hootbro]

I am thinking about trying a different spark plug in cylinder 3 as it can't hurt and pretty easy to access. Also, unless it's just not reading, I really don't show any misfires at start up.

Unless you are popping a CEL, do not waste your time on the spark plug change because I will bet a cold beer it will not change your #3 cylinder having a higher count.

I have gone down this rabbit hole on my 2020 Gladiator with my #4 cylinder showing a higher misfire count. I swapped spark plugs, fuel injectors and coils into other positions and it always remained in the #4 cylinder. Compression and coolant pressure checks were also done and nothing noted as unusual

My 2021 and current 2022 show the same thing of one cylinder having a higher trending misfire count. Just seems to be a thing with these engines. Like others mentioned, unless you are looking at multiple hundred misfire counts that would post a CEL, I would not get too wrapped around why your #3 is doing it.

 

[ShadowsPapa]

Agree. With most of them happening right away and then things settling down, it's not likely a big deal. And consider you are looking at only around 15 to 20 difference from the other cylinders.
If you get into double that, then there could be something to look at, but if it settles down, it's not going to be something you can catch.
Think of the time frame, the number of revolutions, and how many misfires out of the total cycles that really is. Small.

Wait until you see big numbers.

 

[OHJeeper]

On a related note... not bragging but I had mine logging for 30 min and showed zero on any cylinder. Stop and go plus highway. Is that possible?

 

[ShadowsPapa]

No. The last update told the pcm to ignore all misfires or other problems. ?

 

[56cbr600rr]

On a related note... not bragging but I had mine logging for 30 min and showed zero on any cylinder. Stop and go plus highway. Is that possible?

I kind of doubt it. I had the same thing happen recently, but I don’t think the Bluetooth was communicating properly.

 

[ShadowsPapa]

I kind of doubt it. I had the same thing happen recently, but I don’t think the Bluetooth was communicating properly.

If BT isn't communicating, you likely won't get any display of PIDs. JSCAN would tell you, errors.

Misfires are also recorded per session in the PCM so if BT communications was lost, it would catch up when reconnected. The updates are live but the total misfires are pulled from the PCM. (my understanding, at least)

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