There are 3 owner-reported fuel system complaints for the 2018 Kia Optimain NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
THE FUEL PUMP HAS AN ACTIVE RECALL. TOOK ITIN TO DEALER AND WE ARE BEING ADVISED KIA WILL NOT COVER THE COST. THEY HAVE AN ARTICLE OUT THAT CLEARLY STATES THEY WILL COVER THE COSTS. THE CAR WREAKS OF THE SMELL OF GAS AND WE ARE SCARED IT WILL CATCH FIRE.
ECM telling fuel pump to put too much gas, causing exhaust into cabin, unnoticed while in car, but hair and cloth reak of exhaust and getting headaches. Reduced mileage by 20+mpg from 30+ to 11mpg. BSD- no lights or codes thrown by 3rd party, but dealer said there was a code on the BSD. BSD was not working and no codes appeared. NO LIGHTS OR CODES FOR FUEL ISSUE OR BSD, but dealer said there is a recall that I cannot find for fuel and said there was a code for BSD, but it didn’t pop up on my husband’s code reader previously.
Leaking gas at the firewall when running.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026