2012 Kia Optima owners report a pattern of fuel-system failures spanning multiple components. Limp mode is a recurring complaint, with vehicles limiting RPM to 2,000 and speed to 55–61 MPH; one owner reported excessive fuel consumption accompanying the condition. High-pressure fuel pump and fuel pipe failures are documented at relatively low mileage (88,800–111,227 miles), causing hesitation, loss of power, and stalling. One complaint details fuel pump module failure at 162,000 miles with no warning light. Fuel system contamination required complete replacement at 74,000 miles, even though the system had been replaced less than three years prior.
Two owners report vehicle fires during driving—one with intermittent gasoline smell preceding ignition, the other with no warning beforehand. Fuel odor after refueling is reported by another owner. A start-issue complaint describes the vehicle cycling through auxiliary mode (AC and radio on, engine off) before eventually starting after multiple attempts.
Several complaints reference recall 18V907000 (Fuel System, Gasoline, Engine) with mixed outcomes: one owner's fuel rail system and fuel tube clamps were replaced under recall but limp mode persisted despite multiple dealer visits. Another owner's high-pressure fuel pipe was inspected during the recall but not replaced initially, then required replacement after a stall. A third complaint notes the vehicle's VIN was not included in the recall. Recall 20V100000 (Fuel System, Gasoline) issued for an engine-rattling complaint, but parts were unavailable for an extended period.
Failure modes owners describe
Limp mode with power loss
Vehicle enters limp mode, restricts RPM to 2,000 and speed to 55–61 MPH. Owner reported oil control valve failure code; replacement failed to resolve the issue. Dealer replaced fuel rail system, fuel tube clamps, bolts under recall 18V907000, and later battery and engine oil; failure persisted. Accompanied by excessive fuel consumption.
When: 157,000 miles
Symptoms owners cite: Vehicle enters limp mode; RPM limited to 2,000; Speed limited to 55–61 MPH; Cannot exceed 45 MPH uphill; Cannot exceed 55 MPH downhill; Excessive fuel consumption
Codes mentioned: Oil control valve failure
Repairs/costs cited: Oil control valve replaced; fuel rail system, fuel tube clamps, and bolts replaced under recall 18V907000; battery and engine oil replaced; failure recurred despite repairs
Recalls/TSBs owners mention: NHTSA Campaign 18V907000 (Fuel System, Gasoline, Engine); no assistance provided after recall work failed
High-pressure fuel pipe failure
Vehicle stalled while driving; diagnostic identified failure code at high-pressure fuel pipe. Part was inspected during recall 18V907000 but not replaced; subsequently replaced after stall event. Another complaint reported engine rattling with check engine light at 230,000 miles under recall 20V100000; parts unavailable for extended time.
When: 111,227 miles; 230,000 miles (second instance)
Symptoms owners cite: Vehicle stalled during driving; Check engine warning light illuminated; Engine rattling noise; Check engine light remained illuminated
Codes mentioned: High-pressure fuel pipe failure code
Repairs/costs cited: High-pressure fuel pipe replaced after stall; recall 18V907000 inspection found no issue initially
Recalls/TSBs owners mention: NHTSA Campaign 18V907000 (Fuel System, Gasoline, Engine) initially did not replace pipe; NHTSA Campaign 20V100000 (Fuel System, Gasoline) issued but parts unavailable for extended period
High-pressure fuel pump failure
Vehicle exhibited hesitation, loss of motive power, and slow acceleration with check engine light. One complaint reported vehicle deceleration when accelerator was depressed, rattling on acceleration, and oil warning indicator flicker. Diagnostics confirmed high-pressure fuel pump failure in both cases.
When: 88,800 miles; 166,000 miles
Symptoms owners cite: Vehicle hesitation; Loss of motive power; Slow acceleration; Check engine warning light illuminated; Vehicle deceleration with accelerator depressed; Rattling noise during acceleration; Oil warning indicator flickered
Codes mentioned: High-pressure fuel pump failure
Repairs/costs cited: One complaint: high-pressure fuel pump replaced at dealer; second complaint: vehicle not repaired
Recalls/TSBs owners mention: One complaint related to recall 18V907000; no assistance provided in either case
Fuel pump module failure
Vehicle lost motive power with no warning light. Diagnosis confirmed fuel pump module failure. No repair attempted.
When: 162,000 miles
Symptoms owners cite: Loss of motive power; No warning light illuminated
Codes mentioned: Fuel pump module failure
Repairs/costs cited: Fuel pump module replacement needed; vehicle not repaired
Recalls/TSBs owners mention: Manufacturer not notified
Fuel system contamination
Vehicle lost motive power and stalled. Dealer diagnosed contamination in fuel system requiring complete fuel system replacement. Owner noted fuel system had been replaced less than three years prior.
When: 74,000 miles
Symptoms owners cite: Loss of motive power; Vehicle stalled
Codes mentioned: Fuel system contamination
Repairs/costs cited: Fuel system replacement needed; prior fuel system replacement within three years; vehicle not repaired
Recalls/TSBs owners mention: Manufacturer not notified
Fuel odor after refueling
Owner reported abnormal fuel odor inside vehicle immediately after refueling. Linked complaint to recall 18V907000 but VIN was not included in recall. Dealers quoted diagnostic fees; owner declined repairs.
When: Unknown mileage
Symptoms owners cite: Abnormal fuel odor inside vehicle after refueling
Repairs/costs cited: No repair attempted; owners declined diagnostic fees
Recalls/TSBs owners mention: NHTSA Campaign 18V907000 (Fuel System, Gasoline, Engine); VIN not included; manufacturer confirmed VIN exclusion
Vehicle fire
Two complaints reported vehicle fire during driving. First complaint: owner noticed gasoline smell intermittently on highway, then vehicle caught fire near Farner, TN with no warning lights or engine miss. Second complaint: vehicle caught fire at 45 MPH with inability to accelerate or brake; recent service found no issues.
When: Unknown mileage (first); recent service prior to fire (second)
Symptoms owners cite: Gasoline smell while driving; Hot smell preceding fire; Vehicle caught fire; No warning lights (first incident); Unable to accelerate/brake (second incident)
Repairs/costs cited: Vehicles destroyed by fire; no repair possible
Recalls/TSBs owners mention: No response documented
Start/auxiliary mode cycling issue
Vehicle would not start on first button press; entered auxiliary mode instead (AC, radio, lights powered but engine off). After multiple button presses and attempts, vehicle eventually started. One complaint also mentioned brake pedal engagement issue and unrelated turbo actuator problem.
When: Unknown mileage
Symptoms owners cite: Vehicle enters auxiliary mode instead of starting; Multiple start attempts required; AC, radio, and lights powered in auxiliary mode; Brake pedal remained engaged
Repairs/costs cited: No repair documented
Synthesized from 12 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.