PO304 engine code issues

[big5dogg]

It's been a while since I haven't posted anything but I got a 99 sport with the 4.0 ohv engine and everytime I start it, it runs a bit rough for about 5 seconds then it smoothes out. Now check engine light came on with cylinder 4 misfire, so I took out the spark plug and it looked a bit black so I replaced it with a new one. Started the engine again and still runs rough, So I disconnected the #4 cable and it seems to have less resistance in spark compared to the other cables, Would this mean a bad coil? or a bad spark plug cable?

Any help would be appreciated.

 

[1998Exp]

Resistance is proportional to length, so the resistance of a shorter wire is less than that of a longer wire. Most cable failures are not due to increased resistance, but due to a miniscule crack in the insulation, which allows the spark to jump to the nearest metal. Sometimes you can see that in the dark. Otherwise, if you suspect the cable, swap it with one going to a different cylinder (perhaps #1 ) and see if the misfire follows the cable.

It's been a while since I haven't posted anything but I got a 99 sport with the 4.0 ohv engine and everytime I start it, it runs a bit rough for about 5 seconds then it smoothes out. Now check engine light came on with cylinder 4 misfire, so I took out the spark plug and it looked a bit black so I replaced it with a new one. Started the engine again and still runs rough, So I disconnected the #4 cable and it seems to have less resistance in spark compared to the other cables, Would this mean a bad coil? or a bad spark plug cable?

Any help would be appreciated.

 

[big5dogg]

Ok ty. I actually found out that my upper intake is leaking coolant onto cylinder #4 ...