PITSTOP - ENGINE COMPONENT RE-USE GUIDELINES - In general, parts and components removed during engine repairs should be considered serviceable, and should be thoroughly cleaned and transferred to the new engine.
full bulletin at NHTSA ↗2007 Kia Optima engine problems
severe 15 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
15
Recalls
0
Avg fix
$3,100
4fires
When does it fail?
Of the 15 engine complaints filed for the 2007 Kia Optima, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
No new NHTSA engine complaint has been filed on this vehicle in over 15 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
KIA: ECM UPGRADE WITH TP SENSOR REPLACEMENT-MIL ON WITH DTC P2135/P0638. INFORMATION RELATED TO ECM SOFTWARE AND TP SENSOR UPGRADE ON SOME VEHICLES WITH 2.7L ENGINES WHICH MAY EXPERIENCE A MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED WITH THE ELECTRONIC THROTTLE CONTROL (ETC) SYSTEM RELATED DTC P2135 OR P0638 OR P2A00 OR P2A03.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 15 complaints on this 2007 Optima engine cluster describe a pattern of sudden, severe failures. The dominant issue is catastrophic bearing and rod damage: owners report loud knocking under acceleration, metal shavings in oil, and total engine seizure requiring replacement at 62K to 150K miles. One vehicle caught fire during highway driving after owners heard a loud pop; another caught fire shortly after an oil change. Several owners report the engine simply shut down without warning while driving 45–70 mph, with no warning lights beforehand.
One owner experienced extreme oil consumption—2 quarts per week—traced to a faulty crankshaft timing oil control valve that failed to maintain pressure, which the owner believes then sucked air into the engine and damaged the rod. Another complaint alleges that using a non-Kia oil filter introduced metal debris, though the owner notes Kia documentation never required OEM filters. A mechanic stated he has replaced several engines for similar tapping issues but found no official recall covering them.
Kia's response has been inconsistent. The manufacturer acknowledged similar complaints online but excluded many vehicles from recalls. Warranty denials cite the 100K-mile threshold, and one owner was refused help despite an advertised "engine for life" warranty because they lacked five years of service receipts.
Same Kia Optima engine reports on nearby years: 2006 · 2008
Failure modes owners describe
Catastrophic engine bearing and rod failure
Main bearings fail, rods fracture or become damaged, causing metal debris in oil. Leads to total engine loss.
When: 62K to 150K miles; one case at 94K miles (2012 model)
Symptoms owners cite: Loud knocking or tapping in engine, especially under acceleration or climbing hills; Abnormal engine noise; Engine seizure and sudden stalling while driving; Check engine light (intermittent or persistent); High idle without moving; Smoke and fire from engine compartment
Codes mentioned: P0600011, Check engine light (codes not detailed in most narratives)
Repairs/costs cited: Engine replacement required; repairs cited at $7,000. Metal shavings found in oil.
Recalls/TSBs owners mention: Kia acknowledged similar complaints online but excluded affected vehicles from recalls. Denied warranty coverage over 100K miles. Refused repair assistance in some cases.
Excessive oil consumption without external leak
Engine loses 2 quarts per week with no visible leaks or burning. Owner suspects air being sucked into engine due to low oil pressure.
When: Within first 3 years of ownership; preceded catastrophic failure by weeks
Symptoms owners cite: Rapid oil level drop (2 quarts per week); Low oil pressure warning/condition; Check engine light (EVAP-related codes initially, then crankshaft timing code)
Codes mentioned: EVAP leak codes, Crankshaft timing oil control valve fault
Repairs/costs cited: Previous $1800 repair at Firestone for EVAP issue did not resolve underlying oil consumption problem.
Recalls/TSBs owners mention: Kia website contained complaints about same issue; vehicle not covered under recall despite widespread reports.
Sudden engine stall without warning indicators
Engine shuts down abruptly while driving at highway speed with no warning lights or symptoms beforehand.
When: Low mileage (3K-70K miles); intermittent occurrences
Symptoms owners cite: Vehicle stalls while driving; No warning lights prior to stall; Intermittent nature (difficult to diagnose); Shaking and slowing before cut-off in one case
Repairs/costs cited: Dealerships unable to diagnose or replicate failure. Engine replacement needed in at least one case.
Recalls/TSBs owners mention: Dealer advised customer to bring vehicle in for diagnosis but could not identify cause. No repair performed.
Oil filter incompatibility causing engine damage
Use of aftermarket oil filter allegedly introduces metal debris into engine, causing knocking and requiring engine replacement.
When: After oil filter change with non-Kia filter
Symptoms owners cite: Engine knocking shortly after aftermarket filter installation; Metal in engine detected
Repairs/costs cited: Engine replacement needed. Owner reports no Kia documentation required OEM filters; discovered bulletins about this issue online (approximately 2 years old at time of complaint).
Recalls/TSBs owners mention: Kia Consumer Affairs declined warranty coverage citing >100K miles and non-OEM filter use. Dealership refused to honor 'engine for life' warranty without 5-year service receipts. Did not pay for tow or diagnostic fees.
Engine fire and explosion
Engine compartment catches fire and explodes while vehicle is stationary or at highway speed, with flames entering cabin.
When: During normal driving or shortly after adding oil
Symptoms owners cite: Blue or white smoke from engine compartment; Flames visible at transmission and AC area; Loud pop or explosion from engine compartment; Loss of electrical and engine power; Burning shrapnel ejected from engine compartment; Windshield breaks from heat
Repairs/costs cited: Total loss of vehicle. One reported repair estimate $7,000 for hole in engine (fire-related).
Recalls/TSBs owners mention: Not addressed in narratives.
Engine tapping/ticking noise
Persistent engine tapping in idle and motion, unresolved by oil change. Mechanic reported recalls for similar failures on other units but no official recall on owner's vehicle.
When: Complaint lodged at unspecified mileage
Symptoms owners cite: Tapping noise from engine back end; Noise present during idle and while driving
Repairs/costs cited: No repair documented.
Recalls/TSBs owners mention: No official recall exists for this owner despite mechanic stating he has replaced several engines for this issue.
Synthesized from 15 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 3 most recent
Broken crankshaft pulley and drive belt. *tr
I was driving to work and my drivers side airbag came on. A few months prior, we had to replace the o2 sensor because the check engine light was on. Now on the second day with the airbag light on, the check engine light came back on! Is it bad wiring, will my airbag not work? *tr
My Kia optima began consuming large amounts of oil but it wasn't leaking out or burning off anywhere. I began to watch the oil levels closely and was down 2 qts every week. At some point the oil pressure got too low and we think sucked air into the engine. The check engine light came on and then off again as it has been for the ppast yr but for an EVAP problem - a very small leak kept getting…
Had engine trouble with your 2007 Kia Optima?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2007 Kia Optima?
It's a meaningful issue. 15 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Across the 12 complaints that reported odometer mileage, most engine failures cluster between 74,027 and 125,000 miles, with the median around 94,000. A quarter of owners report trouble before 74,027; a quarter make it past 125,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2007/Kia/Optima.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.