I didn't get a read on the old plugs, but what I can do, is pull the ones that are in my engine now, and check their condition. With the high primary resistance found on the coil pack, should I look at replacing it?

 

Here are photos of the plugs out of my '04 2.0. They have approx 2000 miles of in town, and highway driving on them. Photo 1 is cyl 4, second one is cyl 3, third is cyl 2, bottom photo is cyl 1. They are gapped as per spec.

 

Ok good idea to have posted plug photos. Photo-1 cyl 4 plug, is that a piece of carbon between the center electrode & ground lug, or just a out of focus black something or other in the back ground?


Photo-2 cylinder 3 plug, is the dark line at about the 3oclock position a crack in the internal ceramic insulator?

 

On the cyl 4 photo, yes, is just out of focus. I can re check the #2 plug. Bought a good coil at an auto recycler yard, I will take it on a road trip today and see what it does.

 

Check the salvaged coil pack to the FSM resistance readings for the Primary & Secondary resistance values according to the plug wire tower metal contact color.

Maybe call around & see which auto parts store can bench check the coil pack for proper out put voltage. Most can & will perform this bench test at no cost.

Good idea to road test the vehicle, as it'll get everything good & warm, dried out & up to full operating temp. Also include a good steep grade, so you load the engine at low & high speeds, to see if the spark gets under load blow out / misfire.

Another thought about the #3 plug photo, make sure that dark line on the internal insulator isn't a electrical break down carbon track path. If it is, clean it off if you use the plug. A metal, or paint polish & hard wooden stick will usually tidy the insulator up. Blast it clean with a brake or intake manifold, or electrical parts cleaner to get things squeaky clean If it was a carbon track & you have another miss on the road test, add that plug to the suspect list, especially if the computer flags the #3 cylinder with a misfire code.

More thoughts for consideration, let us know how it goes.

 

Took it on a long road trip, 142 miles total, some good hills in the area I was in. Pulled the hills with zero miss,more power than it had. Got 38 mpg for the round trip

 

Ok good feedback, so are you about to color this puppy fixed?

 

Yes, it ran flawlessly from cold this morning till I got home, never missed a beat. Thanks for all the replies and help !

 

Ok, case closed, looks like the salvage coil pack did the trick, good find fix & feedback.

 

The coil I took off was a MasterPro brand from O'Reilly, I was told, by an O'Reilly employee no less, that brand of ignition components aren't the best quality.