P0300 diagnosis. Misfire History counts.

[ZO6_Bryan]

Do I have a problem with cyl #4? It's looks like I do. 2012 ZL1 with a cam. Cam is a pretty smooth idle and has been in the car for a little over a year and never set the P0300 before. But the last couple months it will throw a code randomly. The car runs fine. But rather than just tune out the P0300 I took it seriously and logged everything misfire related. The counts for #4 are significantly higher than the rest. #3 looks high also.
Misfire History starts over at "0" every time the car is restarted. This picture shows what was stored after a 30 min drive.


misfire.jpg

[5FDP]

Check compression?

[schpenxel]

Plugs?

[C5 2000]

raise the Cylinder Mode .

[ZO6_Bryan]

I plan to check the plugs and compression. And I know how to adjust cylinder mode and rev. mode to get rid of the code. I just want to know how to interpret the misfire data. Like I said, the code never appeared before. And the cam has been in there for a year. Am I right that cyl #4 is significant enough to look there first. All cylinders show some misfire counts. And I guess that is normal. But #4 cranks up the counts more than the rest.

[C5 2000]

http://www.hptuners.com/forum/showth...nosis.+Misfire

[C5 2000]

Multiply the Misfire section tables by 1.25 to start.

[ZO6_Bryan]

Multiply the Misfire section tables by 1.25 to start.

I don't want to disable the code. I want to know how much deviation in misfire counts from cylinder to cylinder is normal.

[Niemer]

I know this is an old thread, but wondering if there was any progress on this? I'm seeing something similar, cylinder 6 has ~ 10x the misfire history as the next highest, plugs are new and I don't see any fouling, swapped the coil pack and wire and the problem stayed with 6.

[JBZ]

I know this is an old thread, but wondering if there was any progress on this? I'm seeing something similar, cylinder 6 has ~ 10x the misfire history as the next highest, plugs are new and I don't see any fouling, swapped the coil pack and wire and the problem stayed with 6.

ive wondered the same thing. I log total misfires and on an average day I will get a total of 30 misfires, I don't log each cylinder so I have no idea which ones is seeing though. no cel or dtc either so i guess its somewhat normal to see some and It doesn't seem to have any affect on the car that I notice.

[Southwest Speed]

Fouled plug?

[Niemer]

Nothing that stands out, they all look the same. 1-8 left to right.

P5030167.jpg

[mowton]

Systematically, move (should have said SWAP) the cylinder #4 coil, wire, plug and injector to other cylinders and see if problem moves to a component on another cylinder, if so, that is the bad item.

Ed M

[matty b]

Systematically, move the cylinder #4 coil, wire, plug and injector to other cylinders and see if problem moves to a component on another cylinder, if so, that is the bad item.

Ed M

Listen to this man. You would not believe how many people randomly buy shit when they could verify the issue precisely by doing this.

[Niemer]

I've done the coil and wire, plug and injector are next on the list.

[marksrig]

I've done the coil and wire, plug and injector are next on the list.

So what happened?