P0301 code
 

Hey guy's I have a 98 deville with 131,000 miles and just a few weeks ago i noticed my car would feel like it was missing when I would fire it up at a cold start then it would go away when it warmed up, then this week the engine light came on and i pulled a p0301 # 1 misfire code and the car was missing all the time at idle but runs fine after you get going. I replaced the plugs and wires witch were BOSH for the plugs at 50 degrees gap and the DURALAST 7MM wires then started it and ran good again until i went to the gas station and back and the light came on and started to miss again, so the next thing i tried was changing the # 1 and 4 coil pack but no luck there. Can anyone tell me if they had this problem and what else could cause this #1 cylinder to miss fire? any help on this would be grate thank you.

Did changing the coil pack move the miss to cyl 4, or is cyl 1 still showing a mis-fire?
Sounds like cyl 1 has a problem that is not electrical in nature, but a goofy cam/crank sensor could cause that, too.
I would check compression on all cylinders and compare the readings to see if cyl 1 is low. If compression checked ok, since you have new plugs/wires, and have changed/swapped the coil(s), then I would be looking at an injector malfunction, which could be a bad injector, or simply a harness connector problem.
Also, a small vacuum leak in the area of the #1 intake tract could be a possibility.
hth