I got a service engine soon light and and scanned it. It came out to be cylinder 5 misfire. My truck shook a little on idle more when I gassed it. I talked to some mechanics and told me it would be the coil. So I replaced the coil and the vibration didn't stop. So I went ahead and replaced the spark plug as well. the vibration was different now and now I can smell of burning gasoline. Or the smell of fireworks. Please help.
Are you sure you replaced the #5 coil?
It should be the front driver's side.
If you did, you might have gotten a bad coil. Another thing to try is to swap out the new coil with a different coil and see if the problem worsens or follows where you put the new coil. You could also do this with the old coil to see if the problem follows the coil or if it stays where it's at. If it stays where it's at, the problem is in the wiring. You'll need to follow that back to the ECU and power source to figure out where the break is at.