TECHNICAL SERVICE BULLETIN: TRANSMISSION FLUID APPLICATION GUIDE - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced, and the transmission oil cooler is transferred to the new transmission.
full bulletin at NHTSA ↗2017 Kia Optima powertrain problems
moderate Owners of the 2017 Kia Optima have filed 17 NHTSA complaints about the powertrain at roughly $2,500 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
Complaints
17
Recalls
0
Avg fix
$2,500
| Model year | powertrain complaints |
|---|---|
| 2013 Optima | 56 |
| 2014 Optima | 19 |
| 2015 Optima | 48 |
| 2016 Optima | 66 |
| 2017 Optima (this page) | 17 |
| 2018 Optima | 18 |
| 2019 Optima | 16 |
| 2020 Optima | 24 |
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering powertrain 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.
This bulletin provides information relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced.
full bulletin at NHTSA ↗TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INHIBITOR SWITCH REPLACEMENT (SA317B/C) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides the procedure to replace the inhibitor switch on some 2017MY Optima (JFa), Sorento (UMa), Optima Hybrid (HEV), Optima Plug-in Hybrid (PHEV), Sportage (QL), Forte (YD), and Sedona (YP), and some 2016-2017MY Optima (JF) vehicles, equipped with a front wheel drive 6-speed transmission, which may experience the concerns listed below. These concerns may be due to the inhibitor switch not allowing the correct gear position signal to be sent
full bulletin at NHTSA ↗TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INHIBITOR SWITCH REPLACEMENT (SA317B/C) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides the procedure to replace the inhibitor switch on some 2017MY Optima (JFa), Sorento (UMa), Optima Hybrid (HEV), Optima Plug-in Hybrid (PHEV), Sportage (QL), Forte (YD), and Sedona (YP), and some 2016-2017MY Optima (JF) vehicles, equipped with a front wheel drive 6-speed transmission, which may experience the concerns listed below. These concerns may be due to the inhibitor switch not allowing the correct gear position signal to be sent
full bulletin at NHTSA ↗TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INHIBITOR SWITCH REPLACEMENT (SA317B/C) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides the procedure to replace the inhibitor switch on some 2017MY Optima (JFa), Sorento (UMa), Optima Hybrid (HEV), Optima Plug-in Hybrid (PHEV), Sportage (QL), Forte (YD), and Sedona (YP), and some 2016-2017MY Optima (JF) vehicles, equipped with a front wheel drive 6-speed transmission, which may experience the concerns listed below. These concerns may be due to the inhibitor switch not allowing the correct gear position signal to be sent
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2017 Optima cluster shows two main problem categories: engine and transmission defects, with exceptional oil consumption dominating owner complaints.
Oil consumption affects multiple engine types (GDI, Theta II, turbo GAMMA 1.6) and starts between 34,900 and 85,000 miles. Owners report consuming 1 quart weekly to 1-1.5 quarts every other day, with no visible leaks underneath. Oil accumulates on valve covers and the top of the motor instead. This triggers oil-fouled spark plugs (replaced repeatedly), misfire codes P0303 and P0304, and check engine lights. Kia has acknowledged GDI engine oil consumption as a known issue, but dealerships refuse warranty coverage and offer only upper-engine cleaning as a temporary fix.
Engine failure accompanies oil consumption: sudden loss of power at highway speed (70 mph), loud knocking, burning smell, and complete seizure. One owner's engine failed at 115,900 miles only 4,500 miles after a documented oil change; another needed full engine replacement at 97,769 miles. Repair estimates exceed $14,000.
Transmission problems surfaced after firmware updates. One owner lost all acceleration at 70 mph with multiple dash alerts and hybrid warning light; the dealership later replaced the transmission. Another reported transmission hanging up at 40 mph with elevated RPMs and 20% fuel economy loss after a software update. A DCT owner lost 1st and 3rd gears without warning. Dealers either cannot reproduce the issue or require full transmission replacement.
One owner also discovered a minute crack in the oil pan during service; another facility mentioned a possible class action suit over Kia/Hyundai oil pan material defects.
Same Kia Optima powertrain reports on nearby years: 2015 · 2016 · 2018 · 2019 · 2020
Failure modes owners describe
Excessive Oil Consumption
Engine consumes abnormally high amounts of oil between service intervals, ranging from 1 quart per week to 1-1.5 quarts every other day, with no external leaks visible. Oil accumulates on valve covers and top of engine. Owners report adding 7 quarts over three weeks, or 3 quarts every 3,500 miles. Multiple narratives document this as a recurring issue across multiple engine types (GDI, Theta II, turbo GAMMA 1.6). One owner with 125,000 miles reported 1 quart per week consumption.
When: Begins between 34,900 and 85,000 miles; worsens with time and mileage
Symptoms owners cite: Excessive oil consumption requiring frequent top-ups; Oil fouled spark plugs requiring repeated replacement; Engine misfire codes (P0303, P0304); Check engine light illumination; Power loss and hesitation during acceleration; Engine stalls without warning; Burning smell from engine; Oil visible on top of valve cover and motor with no visible leaks underneath
Codes mentioned: P0303, P0304, P1326, 1326
Repairs/costs cited: Upper engine cleaning mentioned as a band-aid fix by owner; full engine replacement quoted at over $14,000; spark plugs replaced multiple times (June 2024, January 2025); coolant system flushed; PCV valve replaced; coolant temperature sensor replaced; oil pan gasket replaced (3,500 miles later still required 3 quarts of oil); dealership acknowledged as known issue with GDI engines but refused warranty coverage
Recalls/TSBs owners mention: Kia acknowledged GDI engine oil consumption as a known issue; dealership extended powertrain warranty not honored by Kia; dealership offered oil consumption test but not warranty repair; Kia corporate alleged to have refused engine replacement but no claim information provided per owner
Engine Failure / Internal Engine Damage
Engines fail with sudden loss of power, stalling, and burning smells. One owner experienced engine seizure after 4,500 miles from last documented oil change; another reported internal engine failure and timing/oil-flow component failures; another at 97,769 miles required full engine replacement. Owners describe sudden shutdown while driving at highway speeds, loss of power during acceleration, and knocking noises indicating bearing failure.
When: 61,000 miles to 125,000 miles; one instance at 115,900 miles; one at 97,769 miles
Symptoms owners cite: Sudden engine stall and shutdown at highway speed (70 mph); Burning smell from engine; Complete loss of power while driving; Loud knocking noise in engine; Engine seized completely; Danger of stranding operator on roadway
Codes mentioned: P0303
Repairs/costs cited: Full engine replacement required; estimated cost over $14,000; dealer quoted engine replacement along with other engine-related repairs
Recalls/TSBs owners mention: Dealership acknowledged internal engine failure and excessive oil consumption as issue; Kia corporate alleged by owner to have refused engine replacement; no formal recall or warranty coverage applied in narratives
Transmission Control Module / Software Defect (Non-Hybrid)
Multiple owners with automatic transmissions reported problems appearing or worsening after firmware/software updates. One owner experienced complete loss of acceleration at 70 mph with hybrid warning light and multiple dash alerts. Transmission then required complete replacement after software updates failed to resolve issue. Another owner reported transmission hanging up at 40 mph with elevated RPMs (1900-2200) and poor fuel economy after firmware update; dealer wiped transmission memory but issue persisted. A third owner experienced sudden loss of 1st and 3rd gears without warning.
When: After software/firmware updates in 2021 and 2022; one occurrence at unspecified mileage with recent DCT clutch failure
Symptoms owners cite: Loss of acceleration ability while driving; Hybrid warning light and all dashboard alerts illuminated simultaneously; Transmission hangs up at specific RPM (40 mph / 1900-2200 RPMs); Engine shaking and stalling; Poor fuel economy (down 20%); Transmission lugging and sluggish acceleration; Sudden loss of specific gears (1st and 3rd); Whizzing sound before gear shifts; Clunky transmission behavior (hybrid model)
Codes mentioned: transmission-related codes (narratives mention codes but do not specify them)
Repairs/costs cited: Full transmission replacement required in first case; transmission memory wipe performed in second case; dealer diagnostics failed to reproduce issue in at least one case; no parts cost provided
Recalls/TSBs owners mention: Recall notice received January 2022 (inspection only, no software update performed); Second recall notice issued stating prior software update from April 2021 had an error requiring updated software (performed February 15, 2022); dealership performed software update February 15, 2022 that did not resolve issue
Spark Plug Misfires (Oil Fouling)
Spark plugs become fouled with oil, causing engine misfire codes. One owner replaced all four spark plugs June 11, 2024, again January 12, 2025, and again by July 7, 2025 due to recurring oil fouling. Another reported misfire on Cylinder 3 at 34,900 miles. These misfires occur in conjunction with excessive oil consumption.
When: Starts at 34,900 miles; recurring through 7+ months in one case
Symptoms owners cite: Check engine light illumination; Cylinder misfire codes; Oil fouled spark plugs requiring repeated replacement; Recurrence of misfires within months of spark plug replacement
Repairs/costs cited: Spark plug replacement performed multiple times (three times in one case over 7+ months); upper engine cleaning recommended but noted as band-aid solution only
Oil Pan Crack / Oil Leaks
Owner discovered minute crack in oil pan during routine oil change service. Dealer service writer suggested excessive force (pneumatic socket driver) may have caused it during tightening; another facility's general manager detected minute leak and mentioned possible class action suit involving Kia/Hyundai oil pans and bolts due to poor material quality. Narratives reference reports of leaks and oil bolt plugs falling out due to expansion/contraction under duress.
When: Discovered during oil change service at 5 years old vehicle age
Symptoms owners cite: Minute crack in oil pan; Oil leaks; Oil consumption related to pan integrity
Repairs/costs cited: Oil pan replacement needed; possible dealer responsibility for crack if caused during service; reference to class action suit involving Kia/Hyundai oil pans and bolt materials
Recalls/TSBs owners mention: No formal recall mentioned; possible class action suit pending per owner account; manufacturer not directly addressed in narrative regarding pan design
Knock Sensor / P1326 Code
One owner experienced check engine light with knock sensor issue code P1326 while driving, causing engine to nearly stall and limiting speed to 60 mph.
When: Unspecified mileage
Symptoms owners cite: Check engine light flashing; Engine nearly stalls; Speed limited to 60 mph maximum; Hesitation during acceleration
Codes mentioned: P1326
Synthesized from 17 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Vehicle experiences sudden and dangerous loss of power while driving, including hesitation during acceleration, consistent with connecting-rod bearing failure risk known in this model’s GDI engine. Dealer estimate found timing and oil-flow component failures connected to internal engine damage. Vehicle is unsafe to drive and stalls/lacks power unexpectedly, creating a high risk of crash.”
Had powertrain trouble with your 2017 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 powertrain problem on the 2017 Kia Optima?
It's a documented issue but not catastrophic. 17 complaints have been filed. Repairs average $2,500 and most owners catch it before it causes a breakdown.
At what mileage does the powertrain typically fail?
Based on the 17 complaints filed, powertrain issues most often appear around 38,625 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $2,500 for powertrain 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 powertrain?
No active recalls currently cover powertrain 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/2017/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.