Misfires chasing
#1
![Default](https://landroverforums.com/forum/images/icons/icon1.gif)
Chasing multiple cylinder misfire. 3,4 and 6. This 04 4.6 was towed to my house with massive oil leak and no reverse. Have sorted those now Chasing these misfires. I have changed plugs inspected for coolant and checked for combustion gasses in reservoir. It has cheap import direct plug wires. I'm not into throwing parts at this at least until I get it on the road. I can see total misfire count with my autel ap200 but not the count on individual cylinders. My question would be what are the chance 3 plug wires are bad at once? Open to insight. I don't see any glaring anomalies when watching live data but I'm not very versed in that. Vacuum is around 24 at idle. Misfire count is way more at idle. Seems to go away when on the throttle or under load. Appreciate any ideas on what to look at.
#3
![Default](https://landroverforums.com/forum/images/icons/icon1.gif)
yes new gas and additive. Have not done compression I could go that route. It wasn't my first thought as I thought it unlikely 3 would be down. But I'm learning here. It had no codes prior to sitting at my place for probably a couple months. Fixing oil leak( front cover) , xyz switch as well as dropping the tank and cleaning up the rear chassis. Chassis work was last and took the longest. After that is when the codes came up.
#4
Join Date: Jul 2021
Location: Top secret government location
Posts: 244
Likes: 0
Received 60 Likes
on
40 Posts
![Default](https://landroverforums.com/forum/images/icons/icon1.gif)
I've always noticed coil pack miss fires more at idle vs at speed. If you pay close attention to your rig you can feel them before they are bad enough to cause a cel. 2 of those 3 cylinders share the same coil pack. My little lady will let me know when a miss cel is about to start well before I can get it to read.
Faulty O2 sensors can also cause miss fires although mine usually read random missfire on multiple cylinders for O2 sensors vs when the coil packs would go shed give specific cylinders.
If wires are the suspected culprit move the plug wire from a non miss fire cylinder to the miss fire cylinder then clear cels, see where the cel for a miss reappears.
Faulty O2 sensors can also cause miss fires although mine usually read random missfire on multiple cylinders for O2 sensors vs when the coil packs would go shed give specific cylinders.
If wires are the suspected culprit move the plug wire from a non miss fire cylinder to the miss fire cylinder then clear cels, see where the cel for a miss reappears.
#5
![Default](https://landroverforums.com/forum/images/icons/icon1.gif)
I've always noticed coil pack miss fires more at idle vs at speed. If you pay close attention to your rig you can feel them before they are bad enough to cause a cel. 2 of those 3 cylinders share the same coil pack. My little lady will let me know when a miss cel is about to start well before I can get it to read.
Faulty O2 sensors can also cause miss fires although mine usually read random missfire on multiple cylinders for O2 sensors vs when the coil packs would go shed give specific cylinders.
If wires are the suspected culprit move the plug wire from a non miss fire cylinder to the miss fire cylinder then clear cels, see where the cel for a miss reappears.
Faulty O2 sensors can also cause miss fires although mine usually read random missfire on multiple cylinders for O2 sensors vs when the coil packs would go shed give specific cylinders.
If wires are the suspected culprit move the plug wire from a non miss fire cylinder to the miss fire cylinder then clear cels, see where the cel for a miss reappears.
#9
The following users liked this post:
JohnZo (05-02-2022)
#10