Cylinder misfire question
#1
Cylinder misfire question
I have a 1997 Ford Crown Victoria with a 4.6L V8. I know this is an F150 forum but this is a common motor in F150s and after trolling for a while you guys seem pretty knowledgeable so I thought I would throw out my problem and hope for some answers.
Check engine light code showed a cylinder 1 misfire. Partially pulled the plug wires from the passenger side coil pack and all are sparking. Also checked them at the plugs and getting spark. Cleared the check engine light and a 1/2 hour later got another check engine light. This one showed a cylinder 3 misfire. Same passenger coil pack. All still sparking after checking again.
I swapped the coil packs, cleared the code and went for a drive. Check engine light came on, had the code checked and got a cylinder misfire on #3. The misfire did not 'follow the coil pack'.
Originally had a misfire on #1, then #3, swapped coil packs and got an misfire on #3, again. Car only has 58,000 miles and is in very good condition. My next thought is to replace the plug wires. Seems odd to get misfires on different cylinders.
Any insight would be most appreciated.
Lakedawgs
Check engine light code showed a cylinder 1 misfire. Partially pulled the plug wires from the passenger side coil pack and all are sparking. Also checked them at the plugs and getting spark. Cleared the check engine light and a 1/2 hour later got another check engine light. This one showed a cylinder 3 misfire. Same passenger coil pack. All still sparking after checking again.
I swapped the coil packs, cleared the code and went for a drive. Check engine light came on, had the code checked and got a cylinder misfire on #3. The misfire did not 'follow the coil pack'.
Originally had a misfire on #1, then #3, swapped coil packs and got an misfire on #3, again. Car only has 58,000 miles and is in very good condition. My next thought is to replace the plug wires. Seems odd to get misfires on different cylinders.
Any insight would be most appreciated.
Lakedawgs
#2
Ohm tested the coil packs.
Primary passenger side is 2.0 and 2.0, driver side 2.0 and 2.0, should be .3-1.0 Ohms.
Secondary passenger side is 13.85K and 13.37K, driver side 13.35K and 12.65K, should be 6.5K-11.5K Ohms.
I'm thinking this proves the coil packs are bad.
Lakedawgs
Primary passenger side is 2.0 and 2.0, driver side 2.0 and 2.0, should be .3-1.0 Ohms.
Secondary passenger side is 13.85K and 13.37K, driver side 13.35K and 12.65K, should be 6.5K-11.5K Ohms.
I'm thinking this proves the coil packs are bad.
Lakedawgs
The following users liked this post:
curtisking316 (02-06-2016)
#4
Depending on how accurate your multimeter is and how much internal resistance it has, the primary windings could be normal, but I'd say your secondaries are way out. New coils should at least help. Did you maybe swap the #1 and #3 spark plugs when you took them out to check for spark? That could explain the seemingly random jump of the misfire.