96, 4.6L misfiring

[cbrown2]

My car has been misfiring for several days now. It is most noticable when I am in 5th gear and begin a grade on the highway. I changed the plugs and wires and had no improvement. I pulled the diagnositc codes and found "p0303, cylinder 3 misfire" and p0304, cylinder 4 misfire" Can anyone give advice as to my next step?

 

[1tirefire]

Maybe check your coil packs.

 

[cbrown2]

What are coil packs, where are they located and how do I install them? Is there an easy way to search archives of this forum so that I don't ask redundant questions?

 

[TNstanggurl]

coil packs

They are the things that your plug wires are hooked up to on the left and right.They serve the same purpose as a distributor.They are not hard to replace at all.

 

[bierbelly]

Wild guess...either a leak in your exhaust system upstream of the O2 sensors, or a bad O2 sensor.

 

[PG98GT]

Have you made sure your plug wires are fully seated on both the plug and coil packs? Seen a corroded coil pack end cause a misfire, so check it for corrosion. Are they stock plug wires? Maybe you have a bud that'll let you try their good #3 and #4 plug wires? Hope it's not the coil packs because the #3 and #4 are connected to different coil packs.