CrisSi
Member
- First Name
- Cristian
- Joined
- Mar 7, 2020
- Threads
- 15
- Messages
- 29
- Reaction score
- 6
- Location
- Long Island, New York
- Vehicle(s)
- 2018 Honda Civic Si Sedan
- Thread starter
- #1
Hey guys, I just recently purchased a 2018 Civic Si with about 38,000 miles on it back in February and I’m at 44,000 now and I’m having some misfire issues. My car is barely modified unless you’d like to consider a K&N drop in filter and a muffler delete heavy modifications. I only use New York 93 for fuel. I keep getting a misfire in cylinder 3 (P303). You can hear it because My car pops and gurgles while idling but it’s more prominent during a cold start. The car seems to drive fine, I haven’t had any noticeable loss in power or decreased fuel economy. I switched around the placement of the ignition coils and cleared the code but the misfire still persisted in cylinder 3. I checked the plugs and they seemed fine but I still changed them with over priced OEM Honda plugs for safety. I saw live data on a fancy OB2 reader and even after the fresh plugs it still misfired in cylinder 3. The live data showed a misfire count of 15 while idling and about 55 when held at 2000ish rpm. I proceeded to use seafoam fuel injector cleaner but I won’t know the effectiveness of it until my next fill up. The light came back on a few minutes ago and although I didn’t check the codes yet I’m pretty sure it’s gonna be P303 I’m losing hope so I was wondering if anyone on the forum could bestow their knowledge onto me and possibly help me diagnose my problem. Thanks for reading this
Sponsored