A while back I started getting a misfire in my engine. I had terrible acceleration and a very jumpy idling. I wasn't getting any error codes so I looked it up on here. A lot of people said clean the throttle body and use injection cleaner. The throttle body didn't help at all so I used injection cleaner and it helped a little. I figured it was a fuel issue so I replaced the fuel filter and that helped a lot but I was still receiving some form of misfire. I checked the ignition coils 5 we're old one was only 2 years old. The gaskets on the old ones were cracked and I found watery oil pooled in the wells. I cleaned it all up replaced the gasket and two sparkplugs that were in the most pooled Wells. (Note: I checked the cylinders and they were dry so the oil/water I'm assuming came from the cracked coil gaskets. It ran much better after that but I'm still getting a misfire with no error codes. Also if it helps my mpg is 12.1 when it is usually about 15. I've also checked my vacuum lines and they seem to be in rly good shape. Is there a reason I wouldn't be getting a code for a failed spark plug or coil?