NHTSA Complaint #11549767 — 2018 HONDA FIT

At 74k miles my check engine light came on randomly. Took the car to a mechanic, who turned the light off and advised me to tighten the gas cap. A few weeks later the check engine light came back on. Auto zone said a spark plug needed replacement. About a week later the check engine light, along with many other lights came on. After a lot of research I learned that there is a recurring issue with Hondas (plural) and their fueling system due to direct injection. Leading to misdiagnosis, replacing unnecessary parts, only to be left with a check engine light. Luckily, I received a letter from honda informing me of the warranty extension for certain Fits due to carbon buildup and misfires. I took my fit to the dealer and shared my concerns with the service advisor. I took it to the experts in hopes that if it was a misfire with a DTC of P0300-P0304, they would surely get it right the first time. A few hours later I was informed they found DTC P0420, meaning the catalytic converted needed to be changed. Ignition coils were also faulty, therefore affecting the catalytic converter. CC was covered under the emissions warranty but coils were not. They could not/would not replace the CC unless I agreed to replace the coils. Despite me sharing my concerns the advisor failed to mention the DTC for the coils, which turned out to be P0304. I replaced the coils and CC, paid $885. When I read the invoice and saw DTC P0304, I got upset and asked a different advisor why the carbon cleaning wasn’t performed instead of changing the coils. I was told there wasn’t enough carbon buildup to be the root of the problem and that the technician had years of experience and I could rest assured there was no other way. Fine. I take the car, less than 48 hours later, my check engine light comes on again. I take the car back. This time I am told the car is showing DTC P2198 and they recommend replacing the fuel injectors and fuel pipe! No DTC misfire, so unable to perform carbon cleanup.