2004 bad C.O.P. which Cylinder

[Dnny44]

Hi all, back again with a new problem. I have developed what seems to be a bad coil on one the cylinders. I am not getting a code but I can feel the misfires and the Torque Pro app I have hooked to the OBD II port counts my misfires while I drive. My issue is that the expedition doesn't seem to report which cylinder is misfiring to OBD. How can I figure out which cylinder is bad?

Thanks in advance for the help!

 

[stamp11127]

Keep the throttle at the position that the misfires are more pronounced so that it will throw a code.

 

[Skauber]

Check "Test results" in Torque. One of the reasons it's not throwing a code is that it might be a random misfire and not a specific cylinder. It should have logged misfires on individual cylinders in "Test results"

 

[Bedrck47]

Random misfires should throw a P0300 code

Copied from the 2004 service manual
P0300 - Random Misfire
The random misfire DTC indicates multiple cylinders are misfiring or the PCM cannot identify which cylinder is misfiring.

 

[Skauber]

It should, but in certain cases it doesn't. Just because the code hasn't been set, doesn't mean the misfires aren't there. Since the total misfire counter is counting, you may be able to see the misfire counters on individual cylinders under the "Test results" screen in Torque. Other than that, it should be possible to check misfires with FORScan, and the last resort would be a power balance test with an OEM scantool.

 

[Lostneye]

If it's that bad you can unplug one COP at a time and see which does not cause much of a change in idle.

 

[Dnny44]

which of things in test results do you look at to see misfires

 

[Skauber]

Wait until it finishes loading and starts refreshing, then scroll down and look for misfire, it'll indicate several values for each cylinder like "last drive cycle" or similar like that.

 

[jacks3am]

Hell its a 2004, im all for correct diagnosis but at the same time you can get a nice set of 8 coils for around 80 bucks on amazon instead of 50 for 1 and have all new coils, something to consider!

 

[Dnny44]

I do believe the culprit is cylinder #5 but I will check again for sure this weekend when I drive back to Alabama. In response to jack's post what is the consensus on the 8 packs of coils that can be found on amazon for around $50 - $80. I'd like to be able to by the pack and replace as needed.

 

[Lostneye]

All the cheap sets like that are just that cheap. They have a much higher failure rate out of the box and do not last as long. And if it's too good to be true like 8 motorcraft COPs for $50 then it is. They will be knock off junk. Personally I don't mess with them. It's not worth the hassle to me. I replace COPs if they go bad with name brand replacements.