PITSTOP: SMART PEDAL FEATURE - THE SMART PEDAL IS AN INTEGRAL PART OF THE ENGINE MANAGEMENT SYSTEM (EMS) FUNCTIONALITY WHICH MONITORS AND PREVENTS THE SIMULTANEOUS ACTIVATION OF ACCELERATOR AND BRAKE PEDALS. WHEN ENGAGED, THE FEATURE REDUCES ENGINE POWER TO IDLE. MOST CUSTOMERS WILL NEVER NOTICE THE SMART PEDAL FEATURE WHEN ACTIVE, HOWEVER, CUSTOMERS WHO TEND TO REST THEIR FOOT ON THE BRAKE PEDAL WHILE DRIVING MIGHT DESCRIBE A HESITATION OR DELAY SYMPTOM AND NOT REALIZE THAT THE EMS ELECTRONIC CONTROL MODULE IS INTERVENING, AS DESIGNED.
full bulletin at NHTSA ↗2016 Kia Optima cruise control problems
severe Owners of the 2016 Kia Optima have filed 19 NHTSA complaints about the cruise control, typically surfacing around 35,555 miles at roughly $600 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See cruise control across all vehicles →
Failure mileage
Complaints
19
Recalls
0
Avg fix
$600
| Model year | cruise control complaints |
|---|---|
| 2012 Optima | 20 |
| 2013 Optima | 25 |
| 2014 Optima | 12 |
| 2015 Optima | 24 |
| 2016 Optima (this page) | 19 |
| 2017 Optima | 10 |
| 2018 Optima | 6 |
| 2019 Optima | 6 |
2crashes
1fire
2injuries
When does it fail?
Of the 19 cruise control complaints filed for the 2016 Kia Optima, here's the actual mileage breakdown — failures cluster heaviest at 0-25,000 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 cruise control complaint has been filed on this vehicle in over 6 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 cruise control 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.
Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners describe a pattern of acceleration and engine control failures spanning the vehicle's operational life. Unintended acceleration—the car speeding up on its own to 80–100 mph without driver input—has occurred at highway speeds and in neighborhoods, creating collision and injury risks. Conversely, the car sometimes refuses to accelerate despite pedal input and loses power entirely, requiring restart. Cruise control at highway speeds exhibits erratic behavior, hunting up and down around the set point.
Engine stalling while driving, particularly on interstates, leaves owners stranded in dangerous traffic. Multiple owners report severe oil consumption—1–2 quarts between scheduled changes—despite doing regular maintenance. One engine seized at 80,000 miles with less than 1 quart remaining; Kia denied warranty coverage despite proof of regular 5k-mile oil changes.
Rough starts, hesitation during acceleration (especially below 45 mph), jerking or shuddering, and sluggish power delivery plague the car from low mileage onward. Valve noise, knocking, and a sensation that "gear shifting is not smooth" are common. Some cases follow fuel pump or fuel delivery service, with problems persisting or worsening afterward.
Cooling issues include engine overheating at idle with A/C on. Owners reference Hyundai and Kia Engine Litigation (Cases 8:17-cv-00838 and 8:18-cv-02223-JLS-JDE) and Recall Campaign PI1802B, though Kia has classified the latter as a "product improvement" rather than a safety fix. Dealers often cannot diagnose the root cause despite multiple visits.
Same Kia Optima cruise control reports on nearby years: 2013 · 2014 · 2015 · 2017
Failure modes owners describe
Unintended acceleration and loss of acceleration control
Vehicle accelerates on its own without driver input, sometimes to dangerous speeds (80–100 mph), or conversely fails to accelerate despite pedal input. Owners report the car will not respond to throttle commands and must be restarted to regain power. Multiple complaints describe sudden, uncontrollable acceleration creating highway hazards.
When: Occurs intermittently during normal driving, sometimes at low speeds or in traffic. One reported at 1,000 miles, others at 70,000+.
Symptoms owners cite: Vehicle accelerates without driver input, sometimes rapidly to 80–100 mph; Loss of all acceleration; RPMs drop to zero despite pedal pressure; Car will not accelerate past 49 mph (turbo) or 61 mph (regular mode); Delay of several seconds before acceleration responds to pedal input; Engine RPMs increase drastically to 6–7k independently; Throttle unresponsiveness; driver must release and retry pedal multiple times before acceleration engages; Cruise control self-decelerates and re-accelerates unexpectedly at highway speeds
Codes mentioned: Check engine light illumination, Oil pressure warning light, Key-not-recognized indicator (push button turns red)
Repairs/costs cited: Fuel pump replacement, fuel injector service, fuel delivery system service, CVT valve replacement (owner #75 on waiting list). Some dealers performed 'interim repairs' pending permanent part orders. One owner paid $500 out of pocket after warranty coverage.
Recalls/TSBs owners mention: Recall Campaign PI1802B (ECU upgrade) classified as 'product improvement' not safety issue. Kia warranty to 150,000 miles for engine issues mentioned in class action litigation (Hyundai and Kia Engine Litigation, Case No. 8:17-cv-00838 and 8:18-cv-02223-JLS-JDE). Kia has declined warranty coverage for engine replacement in at least one case citing insufficient Carfax service records, despite owner maintaining regular oil changes.
Engine oil burning and low oil condition
Engine consumes excessive oil between scheduled changes, requiring owners to add 1–2 quarts between services. Some owners report oil appearing under the oil pan without visible external leaks. Combined with potential fuel flooding into the cylinder, this contributes to engine seizure.
When: Manifests early in ownership; one owner noted burning at 70,000–80,000 miles. Oil level drops significantly before next scheduled change.
Symptoms owners cite: Rapid oil consumption between oil changes; Engine oil level critically low (less than 1 qt in seized engine case); Oil pooling under oil pan with no external leak visible; Engine seizure from low oil condition
Codes mentioned: Check engine light
Repairs/costs cited: Engine replacement required when seized. One owner's engine seized at 80,000 miles; dealership attempted to deny warranty claiming insufficient Carfax documentation despite regular 5k-mile oil changes using synthetic oil. Kia customer service instructed owner to check oil between changes and declined assistance.
Recalls/TSBs owners mention: Kia warranty extends to 150,000 miles for engine defects related to burning oil and seizure (per class action lawsuits). However, dealers have denied coverage in some instances, citing lack of dealer-service records even when owners produced receipts for regular maintenance at independent shops.
Engine stalling and sudden shutdown during operation
Engine shuts off without warning while driving, typically at highway speeds. Owners report multiple stall events and difficulty restarting. One case involved sudden engine failure on interstate; another involved stalling at a stop sign immediately after fuel pump service.
When: Occurs during normal highway driving. One stall happened shortly after fuel pump/fuel delivery service completion.
Symptoms owners cite: Complete loss of engine power while driving; Check engine light illumination; Knocking noise from engine at shutdown; Difficulty restarting or car shuts off immediately if foot released from gas; Engine stalls at stop signs and traffic lights
Codes mentioned: Check engine light
Repairs/costs cited: Fuel pump replacement and fuel delivery system service performed in at least one case, yet stalling and drivability issues persisted post-service. Owner reported hesitation, strong vibration, and rough starts continuing after fuel system work.
Recalls/TSBs owners mention: Referenced as 'sudden and unexpected engine failure' in Hyundai and Kia Engine Litigation (Cases 8:17-cv-00838 and 8:18-cv-02223-JLS-JDE). Recall Campaign PI1802B mentioned; Kia initially characterized this as a 'product improvement' rather than safety issue.
Rough idle, hesitation, and stumbling acceleration
Engine hesitates, stumbles, or jerks during acceleration, especially from stops or at low speeds below 45 mph. Vehicle feels sluggish and lacks smooth power delivery. Rough or difficult starting reported in some cases.
When: Intermittent; worse in hot or cold weather. Occurs from very low mileage (200 miles reported in one case) through higher mileage.
Symptoms owners cite: Shuddering or jerking forward-and-slow pattern during acceleration; Sluggish response requiring half-pedal depression to gain speed; Engine stumbles to start or struggles to start; Rough idle with engine rumbling as if about to stall; Hesitation before acceleration engages; Fluttering sensation during acceleration until engine picks up speed; Gear shifting does not feel smooth; Unsmooth transmission behavior
Codes mentioned: Check engine light (intermittent or blinking)
Repairs/costs cited: Knock sensor replaced per recall. Fuel injector/pump service and sensor replacement attempted at dealerships with mixed results—one owner had multiple sensors replaced ($206 out of pocket) yet new warning lights continued to appear. Another reported hesitation and strong vibration after fuel system service.
Recalls/TSBs owners mention: Dealers have conducted test drives without reproducing issues in some cases, leaving problems unresolved. One dealership stated inability to diagnose and indicated they would contact Kia for guidance but never provided answers on repeat visits.
Cruise control malfunction and erratic speed adjustment
Cruise control engaged at highway speeds exhibits unpredictable behavior: vehicle self-decelerates several mph below set speed, then re-accelerates past it, creating a 'hunting' effect. One case involved cruise control engaged at 80 mph self-decelerating to 73 mph, re-accelerating to 82 mph, then settling to 80 mph with multiple hesitations beforehand.
When: Occurs during highway cruise control use. One documented at approximately 80 mph after fuel pump service.
Symptoms owners cite: Cruise control self-adjusts speed multiple times (decelerates, re-accelerates) around set point; Vehicle hesitates multiple times before erratic speed changes occur while cruise is active; Unstable speed maintenance during cruise control operation
Repairs/costs cited: Dealership recommended disabling cruise control feature pending further diagnosis. No permanent repair documented in narratives.
Recalls/TSBs owners mention: Dealership instructed owner not to use cruise control feature and to bring car back for service, but no loaner vehicle was available. Recall Campaign PI1802B (ECU upgrade) may address this but not explicitly confirmed in narratives.
Engine overheating at idle with A/C on
Engine temperature climbs above normal when vehicle is idling with air conditioning running. Temperature normalizes immediately when car is in motion. Occurred once severely enough to trigger 'engine overheated' warning on instrument panel at a gas station on a hot day.
When: Occurs when vehicle is stationary with A/C on and engine running. Owner has been cautious post-incident and monitors temperature closely.
Symptoms owners cite: Temperature gauge rising while idling with A/C active; A/C begins blowing warm air; Dashboard warning: 'engine overheated'; Temperature drops quickly once vehicle is in motion
Repairs/costs cited: Owner passed emissions test; AutoZone code reader returned no faults. Owner aware diagnostic test requires 2-day service visit but has not pursued it.
Valve noise and engine ping
Engine produces loud valve pinging and peaking noises during acceleration, persistent regardless of fuel grade used. Combined with A/C power loss and engine miss, suggests combustion or valve timing instability.
When: Present since new vehicle purchase in August 2016, occurs every time vehicle is given throttle input.
Symptoms owners cite: Severe valve pinging and peaking when accelerating; Occurs with all fuel types tested; Engine miss or hesitation coinciding with A/C power loss
Repairs/costs cited: Taken to local Kia dealership six times; no diagnosis has been achieved. Dealership states inability to diagnose and promises to contact Kia without providing resolution.
Synthesized from 19 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 2 most recent
While driving the car the fuel consumption in the motor would bog the engine down to where it would barely go over 40 MPH on the highway. At this time the engine trouble indicator light would come on and not go off. I immediately took it to the local Kia dealership in mt. Hope, wv.. The mechanic changed out the sensor that showed up on his meter and the engine seemed to do good while in the shop…
Tl* the contact owns a 2016 Kia optima. While driving various speeds, the vehicle accelerated independently and the engine rpms drastically increased to 6 or 7. The contact also stated that the check engine warning indicator illuminated and there was a burning odor coming from the engine. In addition, the vehicle was leaking oil. The vehicle was taken to the dealer where it was diagnosed that the…
Had cruise control trouble with your 2016 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 cruise control problem on the 2016 Kia Optima?
It's a meaningful issue. 19 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $600.
At what mileage does the cruise control typically fail?
Across the 9 complaints that reported odometer mileage, most cruise control failures cluster between 32,200 and 57,529 miles, with the median around 35,555. A quarter of owners report trouble before 32,200; a quarter make it past 57,529. 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 $600 for cruise control 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 cruise control?
No active recalls currently cover cruise control 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/2016/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.