Problems · by component
2018 Kia Sportage engine problems
91 owner complaints to NHTSA about the 2018 Kia Sportage cite engine, 55% of all 165 complaints for this model year.
Complaints
91
55% of all complaints
Crashes
0
Reported by owners
Fires
9
Reported by owners
Injuries
1
Reported by owners
What owners say about the engine
Verbatim from NHTSA complaints, newest first
“The vehicle suffered a primary connecting rod bearing failure covered under the Theta II class action warranty campaign. A brand-new warranty engine long-block was installed by an authorized dealership. Immediately upon vehicle pickup, the brand-new engine began exhibiting an un-metered acceleration defect. While stationary and idling in Park (P), the engine aggressively revs on its own without any operator input on the gas pedal. This malfunction caused the vehicle to violently surge and physically lurch forward several inches while in Park. This un-metered acceleration is an active, unpredictable driving hazard both in parking environments and in traffic, posing an immediate risk of a collision or pedestrian injury. The manufacturer has been notified but has failed to transmit a diagnostic pre-authorization to an alternative service center to safely inspect this powertrain hazard.”
“Shortly after driving away, before reaching a highway on-ramp, I noticed smoke coming from the vehicle. I turned around and returned to the location. By the time I arrived, the vehicle was emitting black smoke, and shortly after, it was fully engulfed in fire before I could retrieve a fire extinguisher. Vehicle has a documented history of a known manufacturer recall related to an electrical/HECU component and a separate high-pressure fuel pipe recall, both reportedly remedied prior to this incident”
“Purchased my Kia on the XXX then on the XXX, My engine light came on and my car went into Safety Mode . I at once took it to Auto Zone and their test came back with P1326 Knock signal range / performance. I then looked it up and found that a recall was put out quite a while back called an [XXX] # took my car to Kia Dealership in [XXX]. They said I could bring it in that was on the XXX and if an appointment came open they would check but they did not have an opening til the 14th which was today and I was told it would be next week . Could someone please send me updated information concerning the 2018 Kia Sportage and the Knock Sensor [XXX] [XXX] [XXX] [XXX] [XXX] [XXX] [XXX]”
“2018 Kia Sportage (78,051 miles). Vehicle is part of the Kia Engine Class Action Settlement due to severe internal engine defects. The engine suffers from catastrophic oil consumption, running almost completely dry three times in less than six months with no external leaks, meaning it is internally burning motor oil at a dangerous rate.This known engine defect caused severe consequential damage to the exhaust and emissions systems. On Aug 12, 2026, a Kia dealer technician diagnosed active code P0420. The technician's video inspection stated both the catalytic converter and O2 sensors are completely "out of specification." This double failure is a direct result of the engine defect blowing excessive liquid motor oil out of the engine block and down the exhaust pipe, fouling the sensors and melting the internal catalyst.This failure happened immediately after receiving the mandatory Kia Recall SC340 update (Catalyst Overheating Protection). The vehicle is under the 80,000-mile Federal Emissions threshold, but Kia is denying coverage based strictly on a calendar time limit. They refuse to take responsibility for emissions components destroyed by their…”
“The contact owns a 2018 Kia Sportage. The contact stated that while driving approximately 45 MPH, the vehicle lost automotive power with the accelerator pedal depressed. The check engine warning light was illuminated. The vehicle was taken to a dealer where it was diagnosed and determined that the engine needed to be replaced. The vehicle was repaired; however, the failure persisted. The manufacturer was not notified of the failure. The failure mileage was approximately 64,813.”
“The engine consumes excessive oil due to the known Theta II piston oil control ring defect that the manufacturer documents in its own Technical Service Bulletin ENG222, covering this engine family across model years 2011 to 2024. The vehicle loses over one quart of oil per 1,000 miles with no external leak and no oil pressure warning. The manufacturer's authorized dealer completed the entire TSB ENG222 diagnostic protocol, which is itself a controlled test designed to isolate cause. The engine was sealed, and after 1,080 miles it was 1.5 quarts low. The dealer then performed the TSB's combustion chamber cleaning. After that repair, over 1,149 miles, the engine was 1.4 quarts low. The cleaning had virtually no effect on the consumption rate. Because the protocol sealed the engine and cleaned the combustion chambers and the consumption rate remained unchanged, the protocol itself mechanically excludes maintenance as the cause and isolates the failure to the internal piston rings. This is the exact defect TSB ENG222 was created to diagnose and repair. The defect has been reproduced and confirmed by the manufacturer's own authorized dealer through this protocol,…”
Showing 6 of 91 reports. Read every report on NHTSA.gov.
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 3, 2026NHTSA vehicle page
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.