Kelslogan

Recently my remote start quit working. I assumed it was a weak fob until I noticed my battery voltage was 15V. Knowing my battery was weak, I continued to drive it until it stopped starting. I replaced the battery, and upon trying to start the vehicle it would crank but would never actually start. There was a check engine light being thrown. I didn’t have my code reader on me at the time so I called the local dealership for guidance. They said it could be the fuel pump, but when asked to try to start the vehicle, it started just fine out of now where with no codes or light. I drove it to work and home from work lastnight. This morning I went to start it and again it’s cranking but won’t actually start. The check engine light is back on so I checked the codes with my reader. This is a $100 reader, so not an inexpensive reader, and it didn’t show any codes. I do suspect my catalytic converters are going out because if you hard accelerate there is a strong sulfur smell and my fuel mileage has declined. Do any of you know why I would be having this issue after a battery replace? Why am I showing a check engine light, but not throwing any codes? Am I looking at a failed fuel pump, or is this tied to my cAtalytic converters somehow?