[normabeans]

I got these codes

P0300 (Random Misfire)
P0301 (Random Misfire Cylinder 1)
P0303 (Random Misfire Cylinder 3)
P0316 (Misfire at Startup at 1000 rpm)

I just replaced all plugs, wires, and my cam sensor recently. I brought the car to advanced to get it coded and all i got was misfiring in cylinders 1 and 3, than I replaced all of the plugs and there was less sputtering from the engine. So I don't think its the plugs or the wires, anyone can help.

[1989gtfifty]

year,make,model, check ur timing

[supercharged302]

sound like you have not got your plug boots all the way on

[normabeans]

Its an 04 V6 3.8 , and I thought it was the boots on them, but I made sure they were on. I mean its possible.. But I heard and felt all of them click on

[shinerstang]

There are a few things to check:

1. Coilpack
2. EGR Valve
3. Plugs in the 1 & 3 cylinders
4. Fuel pressure
5. Compression in all cylinders

This is only a start, but I would check the plugs first. Did you purchase the stock wires or generics?

[normabeans]

I got the high performance spark plugs and wires, they are a lot different than the originals, I believe there Bosche.

(Added)
Before I changed my spark plugs it was at a rough idling state, the engine was shaking a lot more than it was. But you can smell the odor from the gas more than you could. The muffler is also shaking.. I'm assuming its just from the misfiring..

[232-K7]

did you replace each plug and wire one at a time?

[normabeans]

I went out and bought a coilpack fixed the problem... I didn't wanna spend the 90 bucks, thanks all

[236Mustang]

nice....