I have a ''93 Ranger w/4.0. When driving home the other night, the check engine light came on and the engine lost a lot of power and seemed to be running on just a couple cylinders. I changed the plugs and the next morning it ran fine for 3-4 miles and did the same thing. Could this be a problem with the coil pack? Any input would be appreciated.

 

how did the old plugs look when they came out? and did you change the wires with the plugs?

 

I did not change the wires. 1 plug had some oil on it, the others were tan looking

 

thats normal except for the oil change the wires and if it continues then maybe change the coil pack they rarely go bad but anything can break really.