788 federal complaints, and the V6 is the only version with a free engine behind it.

Separately from the recall, Kia runs Warranty Extension Program WTY035 on 2016 and 2017 Sorentos with the 3.3-litre GDI Lambda II engine built between October 2014 and April 2017. GDI means Gasoline Direct Injection, fuel sprayed straight into the cylinder. The bulletin tells dealers to "diagnose a coolant leak from the cylinder head gasket area and, if necessary, replace the engine sub-assembly", and states that "the warranty coverage for related repairs will be extended from 5 years / 60,000 miles to 15 years / 180,000 miles, whichever comes first, starting from the date the vehicle was first put into service." The symptoms Kia lists are a coolant leak, a coolant smell, or the temperature needle sitting near the H mark, and it warns that if the car keeps being driven unrepaired "the engine may overheat and become further damaged." On a nine-year-old V6 Sorento this is the single most valuable thing to check.

The four-cylinder file reads exactly like 2016's. Theta II is the Hyundai-Kia four-cylinder family; here a 2.4-litre GDI, with a 2.0-litre turbocharged version above it. The connecting-rod bearings — the metal shells the piston rods spin on — wear early, and the failures in this year's filings arrive with almost no notice. One owner: "the engine in our 2017 Kia Sorento SXL developed a sudden, loud knocking noise while driving. No dashboard warning lights illuminated." Another: "The car started sticking when driving then a knocking in the engine. Upon investigation/diagnostics we found that the engine is blown and needs repl[acement]." Oil consumption runs ahead of it: "The car is consuming oil under the 3,000 mile mark" and "This uses oil. It takes 16 ounces or more every 400 miles." Kia's free knock-sensor software covers this car — and Kia's engine short-block warranty extension does not, as explained below. An independent repair channel covering this generation puts the bill at roughly $6,000 to $8,000 for a replacement engine.

Kia's Product Improvement Campaign PI1802 — a Product Improvement Campaign is a free fix Kia offers outside the safety-recall system — installs the Knock Sensor Detection System, or KSDS, on this car. Kia's own owner letter defines the scope precisely: the software goes on "all 2016-2018 MY Sorento vehicles equipped with 2.4L Gasoline Direct Injection ('GDI') and 2.0L Turbocharged GDI ('T-GDI') engines to protect the engine from excessive connecting rod bearing damage. The update will be done free of charge." The technical bulletin explains the mechanism: the system "detects vibrations indicating the onset of excessive connecting rod bearing wear." A follow-up bulletin, PI1802Y/Z, is titled engine replacement instructions for diagnostic trouble code P1326 — the code the system stores. Here is the part that decides the money. Kia's engine short-block warranty extension for the Sorento, WTY008, covers "2012-2014 MY SORENTO 2.4L GDI ENGINE" and raises coverage on the block, crankshaft, bearings, connecting rods and pistons to ten years or 120,000 miles. It stops at the 2014 model year. Nothing in Kia's Sorento bulletin file extends engine coverage to a 2017 four-cylinder.

Recall 18V907 applies to 2012 to 2017 Sorentos "that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign." On those cars the high-pressure fuel pipe at the fuel-pump outlet "may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak", and a fuel leak near hot metal is a fire. Free inspection and replacement, Kia code SC172. This matters more on a 2017 than almost any other year, because between the crankshaft recall and the bearing failures a large share of these cars are running a second engine. Ask outright whether the engine is original.

Recall 22V703 covers 2016 to 2022 Sorentos fitted with a Kia tow-hitch harness, factory-fitted or dealer-supplied. Debris and moisture on the module's printed circuit board "may cause an electrical short, which can result in a fire", parked or driving, and Kia advises parking outside and away from buildings until it is repaired. Free fuse and/or module replacement, Kia code SC249. Recall 16V862 covers 2016 and 2017 Sorentos built between October 2014 and August 2016 that carry the accessory trailer-hitch harness: a tow-module fault can leave the trailer brake lights permanently illuminated, failing federal lighting standard FMVSS 108 and confusing drivers behind you. Free harness, Kia code SC142. Both remain open on this year.

Kia extended three separate warranties that reach this car, all of them documented in its bulletins and none of them advertised. WTY023 raises coverage on the Motor Driven Power Steering unit — the electric motor that assists the steering, also called Electronic Power Steering — on 2016 and 2017 Sorentos from 5 years and 60,000 miles to 15 years and 150,000 miles. WTY031 covers the multifunction switch knob on 2016 to 2018 Sorentos built at Kia's Georgia plant, which "may exhibit an intermittent headlamp flickering", also to 15 years and 150,000 miles; an independent repair channel calls headlight failures one of the defining faults of this generation. WTY026 covers an oil-pressure-switch leak on 2014 to 2018 cars, raised from 10 years and 100,000 miles to 15 years and 150,000 miles. If the oil light flickers at idle, that is the switch Kia is talking about, and it may cost nothing.

A smaller but serious cluster in the 2017 file is fire. "Engine caught on fire while driving down the hhighway in SC"; another describes smoke and then flame after a loss of power; a third reports "a loud bang from the engine, smoke rolling out of" the bonnet at interstate speed. A related theme is what happens after a replacement engine goes in: "Following an engine replacement performed at [a Kia dealer], I began experiencing persistent electrical system failures." None of this is a recall on its own, but it is the reason the two fire-risk campaigns on this car — 22V703 and, on re-engined cars, 18V907 — should be closed before the car is parked in an attached garage.

Two more free campaigns touch this car. SC340 is a voluntary emissions service campaign that upgrades the engine control module software on 2016 to 2020 Sorentos with the 2.4-litre Theta II engine, because Kia found that some of these engines "may have engine calibrations that were not optimized for emissions standards under certain specific conditions." And CS2304 upgrades the body-control software on 2016 to 2020 Sorentos to restrict the ignition if the locked car is broken into without the key, with CS2312 adding a reinforced ignition-cylinder protector and decals; Kia's owner letter describes the software as addressing "the social media theft method" and says it has been free at authorised dealers since 2023. Neither is a safety recall. Both are worth confirming by name at a Kia service desk, and the anti-theft work is worth confirming before you get an insurance quote.