The 2004 Kia Optima has no open NHTSA recalls. Owners report 7 recurring issue clusters, led by “Door lock and latch failure, driver-side door will not open.” Kia uses Hyundai Motor Group's powertrains, so service intervals mirror Hyundai's. Kia Promise covers the first 3 years / 36,000 miles of complimentary maintenance. Kia owners with the Theta II 2.0L/2.4L (Optima, Sorento, Sportage 2011-2019) should adhere strictly to oil intervals due to known oil-consumption issues in Kia TSBs.
No open recalls on file. NHTSA lists no unrepaired safety recalls for this year, make and model. A recall can be issued at any time, and a specific car can still have one open — check yours by VIN at nhtsa.gov/recalls.
What drivers and federal regulators have officially reported about the 2004 Kia Optima.
LATCHES/LOCKS/LINKAGES
122 NHTSA complaints · 2007-08 → 2022-08
“DRIVER DOOR WOULD NOT OPEN FROM INSIDE OR OUT. POWER DOOR LOCK WOULD AUTOMATICALLY RE-LOCK ALL DOORS WHEN ATTEMPTING TO OPEN OR UNLOCK WITH KEY OR INSIDE LOCK LEVER”
“THE DRIVER'S SIDE DOOR WILL NOT UNLOCK FROM EITHER THE INSIDE OR OUTSIDE. THE KEY WON'T WORK”
“THE CONTACT TOOK THE VEHICLE TO THE DEALER AND WAS INFORMED THAT THE LOCK ACTUATOR HAD FAILED”
SUSPENSION
18 NHTSA complaints · 2009-08 → 2025-02
“When he took off the cover to replace the control arm, he found the sub frame had rotten and was cracking”
“THE CONTACT DROVE ONTO THE EMERGENCY LANE AND NOTICED THE FRONT DRIVER'S SIDE SUSPENSION AND FRAME COMPLETELY FRACTURED DUE TO RUST CORROSION”
“THE MECHANIC DISCOVERED THERE WAS SEVERE CORROSION ON THE SUB FRAM WHICH WOULD NEED TO BE REPLACED”
SEAT BELTS
4 NHTSA complaints · 2011-08 → 2013-08
“IT WAS TAKEN APART AND FOUND THAT THE INNER WORKINGS OF THE SEAT BELT ARE PLASTIC AND A SMALL PLASTIC CLIP THAT HOLDS THE SPRING BROKE, THUS A NON WORKING SEAT BELT”
“THE CONTACT STATED THAT THE REAR DRIVER'S SIDE SEAT BELT WOULD NOT RETRACT PROPERLY”
“THE DRIVER'S SIDE SEAT BELT BUCKLE BECAME DETACHED FROM THE SEAT UNDER NORMAL USE”
AIR BAGS
13 NHTSA complaints · 2008-04 → 2016-10
“DASHBOARD AIRBAG INDICATOR LIT. CODE B1378 PULLED BY THE DEALERSHIP - DRIVERSIDE SIDE AIRBAG RESISTANCE HIGH”
“PURCHASED A 2004 KIA OPTIMA IN 11/2005 AND HAVE REPORTED AIR BAG LIGHT COMING ON EVERY COUPLE OF MONTHS”
“AIRBAG LIGHT REMAINS ON SHOWING A PROBLEM WITH THE SYSTEM”
ENGINE AND ENGINE COOLING
10 NHTSA complaints · 2007-09 → 2017-02
“THE CONTACT WAS DRIVING 35 MPH WHEN THE VEHICLE LOST POWER”
“I WAS ON MY WAY TO WORK AND MY CAR JUST STOPPED RUNNING WHILE I WAS DRIVING ON THE HIGHWAY. I GOT IT TOWED, IT IS THE CRANKSHAFT POSITION SENSOR, THE COST TO REPAIR $460”
“THE CONTACT WAS DRIVING 70 MPH WHEN THE VEHICLE STALLED WITHOUT WARNING. HE WAS ABLE TO RESTART THE VEHICLE BUT THE FAILURE RECURRED SHORTLY AFTER”
FUEL SYSTEM, GASOLINE
6 NHTSA complaints · 2007-10 → 2022-02
“THE VEHICLE WAS TOWED TO THE REPAIR SHOP AND IT WAS DISCOVERED THAT THE ELECTRIC WIRE FOR THE FUEL PUMP HAD BURNED INSIDE THE GAS TANK”
“CAR WAS DIFFICULT TO START AFTER FUEL FILL-UP. IT GOT WORSE AFTER EACH FILL UP”
“The contact stated that after refueling, the vehicle would not start”
SUSPENSION
4 NHTSA complaints · 2008-11 → 2013-08
“AS DESCRIBED BY OTHERS DRIVER SIDE LOWER BALL JOINT ON '04 KIA OPTIMA BROKE WITH 1 SHEARED BOLT AND 1 BOLT JUST FALLING OUT (RUSTED WITH NO CLEAN AREAS)”
“WHILE DRIVING 20 MPH OUT OF A PARKING LOT, THE FRONT PASSENGER SIDE LOWER BALL JOINT AND AXLE DETACHED FROM THE VEHICLE”
“RT BALL JOINT/AXLE BROKE WHILE DRIVING ON 10 OCT 08”
Issues on other model years
Source: NHTSA Office of Defects Investigation (ODI). Complaint data refreshed Sep 20, 2026. Investigation data refreshed Sep 20, 2026.
We display NHTSA's record with attribution; we don't editorialize on what these complaints mean for any specific vehicle.
Critical for safety and preventing major damage
Severe service: every 3,750 miles. Normal: 7,500 miles. Theta II 2.0L/2.4L on Optima, Sorento, Sportage (2011-2019): full synthetic only, never extend.
Estimated cost — typical U.S. ranges
Dealer
~$120–$160
Shop
~$85–$115
DIY
~$25–$55
Full synthetic costs more than conventional. 5-quart 0W-20 + filter is the typical bill.
Rotate tires every 7,500 miles. Telluride and Sorento AWD owners benefit from rotation every 5,000 miles to prevent uneven wear.
Estimated cost — typical U.S. ranges
Dealer
~$85
Shop
~$60
DIY
Free
Often free at the shop where you bought the tires — worth asking before paying.
Inspect brake pads and rotors every 7,500 miles. Forte and Soul front pads typically last 40,000-55,000 miles.
Estimated cost — typical U.S. ranges
Dealer
~$85
Shop
~$60
DIY
Free
Most shops do this free as a courtesy with any service. Don't pay separately if you can avoid it.
Replace DOT 3 brake fluid every 30,000 miles or 24 months. Required for ABS and ESC pump longevity.
Estimated cost — typical U.S. ranges
Dealer
~$180–$200
Shop
~$125–$140
DIY
~$10–$25
DOT 3 or 4 — match the cap. Vacuum bleeders make this a one-person DIY.
Keeps your vehicle running smoothly and efficiently
Replace engine air filter every 30,000 miles. Severe or dusty conditions: 15,000 miles.
Estimated cost — typical U.S. ranges
Dealer
~$60–$95
Shop
~$45–$70
DIY
~$15–$40
5-minute job on most cars; the airbox lid usually has clips, no tools needed.
Severe service: every 30,000 miles. Normal: 60,000 miles. Use Kia SP-IV — same as Hyundai.
Estimated cost — typical U.S. ranges
Dealer
~$330–$500
Shop
~$235–$355
DIY
~$60–$180
Some sealed transmissions have no dipstick — fill is precise and best left to a shop. Many drivers can still DIY drain-and-fill.
Iridium-tipped plugs rated 105,000 miles on most Kia engines. 1.6T (Forte GT, Soul Turbo): 60,000 miles. 3.5L Lambda II V6 (Telluride, Sorento): 105,000 miles.
Estimated cost — typical U.S. ranges
Dealer
~$285–$390
Shop
~$200–$275
DIY
~$25–$100
Iridium plugs cost more but last 100k+ miles. V6/V8 access varies wildly — some are tough.
Kia Long-Life Coolant (pink, same as Hyundai): first change at 60,000 miles, then every 30,000. Do not mix with green or orange coolant.
Estimated cost — typical U.S. ranges
Dealer
~$285–$330
Shop
~$200–$235
DIY
~$25–$60
Use the manufacturer-specified coolant — wrong color/chemistry can damage the cooling system.
On AWD models, replace transfer case fluid and rear differential fluid every 60,000 miles.
Estimated cost — typical U.S. ranges
Dealer
~$105–$140
Shop
~$75–$100
DIY
~$15–$40
AWD/4WD vehicles only. Easy drain-and-fill on most platforms.
Extends the life of your vehicle and improves comfort
Replace cabin air filter every 15,000 miles. Located behind the glove box on Optima, Forte, and Sportage; behind the dashboard panel on Telluride.
Estimated cost — typical U.S. ranges
Dealer
~$60–$95
Shop
~$45–$70
DIY
~$15–$40
Usually behind the glovebox. Shops charge labor for a 10-minute job — easy DIY win.
Occupant deaths in fatal crashes (FARS)
133 crashes 1990–2024
How the 133 occupant deaths break down
100
driver deaths
33
passenger deaths
133
occupant deaths
Crash years covered: 1990–2024 This model year first appears in 2003 crashes. Older models have had more years on the road to appear in these crashes, so a higher count here does not by itself mean a vehicle is less safe.
FARS counts every occupant death in a fatal crash, whatever the cause — it does not mean the vehicle was at fault or defective. Counts are not adjusted for how many of each vehicle are on the road. How to read this number
FARS 2024 data is an annual report file. NHTSA revises these records when the final file is published, so this count can change.
Every vehicle has exactly one driver seat, so driver deaths line up fairly when you compare one model to another. Occupant deaths include passengers, so a three row SUV can show a higher number than a two seat car simply because it carries more people.
Both figures are plain counts, not rates. A rate would need to know how many of each vehicle are on the road, and that registration data is not public, so we do not publish rates or scores of any kind.
IIHS publishes driver death rates using this same driver only idea, paired with a registered vehicle years denominator we do not have. Their rates and these counts answer different questions, so do not read either number here as a safety rating.
Owner-reported problem signals
Separate from the federal fatality data above: complaints owners filed with NHTSA about this year and model. These are reports of problems, unverified, and are counted here only as signals.
8
complaints mentioning a crash
3
complaints mentioning a fire
Typical U.S. ranges. Actual quotes vary by shop, parts choice, and vehicle condition.
How we estimate: Dealer = OEM parts × 1.4 + labor × $165/hr. Shop = parts + labor × $115/hr. DIY = parts only.
This maintenance schedule for the 2004 Kia Optima reflects Kia's published service intervals and the Service Reminder system. Your actual service needs may vary based on driving conditions, climate, and vehicle usage. Always consult your owner's manual for model-specific recommendations.