The 2021 S90 uses Volvo's SPA platform with the T5/T6/T8 powertrain family — all variants of the 2.0L turbocharged four-cylinder. While refined, these engines have documented oil consumption and PCV system issues that can escalate into catastrophic internal failures if neglected. Transmission mounts and cooling systems also show premature wear.
Excessive Oil Consumption & PCV System Failure Leading to Engine Damage
Common · high severity
Typical onset: 40,000-80,000 mi
Symptoms: Oil level drops 1+ quart between changes, Blue smoke from exhaust on cold start or acceleration, Check engine light with P0011/P0014 camshaft timing codes, Rough idle, hesitation, or misfires in severe cases, Sludge buildup visible on oil cap or valve cover
Fix: PCV system replacement involves oil trap, hoses, and diaphragm — 3-4 hours labor. If ignored, causes carbon buildup and oil starvation leading to spun bearings, scored cylinders, requiring complete engine rebuild or short block replacement at 40-60 hours labor plus parts.
Estimated cost: $800-1,500 for PCV repair; $12,000-18,000 for engine rebuild or short block
Transmission Oil Cooler Failure and Coolant Contamination
Occasional · high severity
Typical onset: 50,000-90,000 mi
Symptoms: Transmission slipping or delayed shifts, Milky or pink-tinged transmission fluid (coolant mixing), Overheating transmission or engine temperature warnings, Rough or erratic gear changes, Loss of coolant without visible external leaks
Fix: Internal oil cooler in radiator fails, allowing coolant and ATF to mix. Requires radiator replacement, transmission flush (possibly multiple), and often torque converter replacement if contamination is severe. Total 8-12 hours labor for full repair plus transmission inspection.
Estimated cost: $2,800-5,500
Transmission Mount Collapse
Common · medium severity
Typical onset: 30,000-70,000 mi
Symptoms: Clunking or banging when shifting from Park to Drive/Reverse, Vibration felt through cabin at idle, Drivetrain shudder during acceleration, Visible sagging or torn rubber on mount inspection
Fix: The torque mount (upper transmission mount) fails prematurely on SPA platform. Replacement requires lifting powertrain slightly — 2-3 hours labor. Use OEM or upgraded polyurethane mounts for longevity.
Estimated cost: $450-750
Aisin 8-Speed Transmission Valve Body and Shift Quality Issues
Occasional · medium severity
Typical onset: 60,000-100,000 mi
Symptoms: Harsh or delayed 2-3 or 3-4 upshifts, Shuddering during light throttle acceleration, Transmission 'hunting' between gears at highway speeds, Occasional limp mode with transmission fault codes
Fix: Valve body solenoids stick or fail due to ATF contamination. Requires transmission pan drop, valve body removal, and solenoid replacement — 6-8 hours labor. Adaptive reset required after repair. Sometimes full valve body replacement needed.
Estimated cost: $1,800-3,200
ABS/Traction Control Module Software Glitches and Sensor Failures
Occasional · medium severity
Symptoms: ABS/DSTC warning lights illuminated, Traction control unexpectedly intervenes on dry pavement, Loss of stability control functionality, Harsh ABS activation at low speeds, Intermittent loss of power steering assist (related to stability system)
Fix: Software recall addresses some cases, but wheel speed sensor corrosion and ABS module internal faults also occur. Diagnosis 1 hour, sensor replacement 1-2 hours per corner, module replacement/programming 3-4 hours if needed.
Estimated cost: $300-600 per sensor; $1,500-2,500 for module replacement
Fuel System Contamination and Filter Clogging
Rare · medium severity
Typical onset: 50,000-80,000 mi
Symptoms: Hard starting or extended cranking, Loss of power under load or at highway speeds, Engine stumbling or surging, Fuel pressure fault codes, Check engine light with lean codes
Fix: In-tank fuel filter not regularly serviced leads to pump starvation. Requires fuel tank drop, pump/filter module replacement — 4-5 hours labor. Some cases involve contaminated fuel from bad gas causing injector damage requiring additional cleaning or replacement.
Estimated cost: $800-1,400 for pump/filter; add $600-1,200 if injectors need service
Owner tips
Check oil level every 1,000 miles — these engines are known oil consumers even when healthy; top off to prevent starvation damage
Use manufacturer-specified 0W-20 full synthetic only and stick to 5,000-mile oil change intervals to minimize PCV and carbon buildup issues
Inspect transmission fluid color and level at every oil change — early detection of cooler failure saves the transmission
Address any vibration or clunking immediately — transmission mount failure accelerates other drivetrain wear
Budget $1,000-1,500/year for deferred maintenance items if buying used; PCV and mount refresh should be done preventively around 60k miles
Buy only with comprehensive service records showing PCV maintenance and oil consumption monitoring; budget for inevitable transmission mount and potential engine work — not a carefree ownership experience despite the luxury badge.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
Fitment notes: AGM battery required for start-stop system; located in trunk
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Every control module on the 2017-2026 Volvo S90 — where it lives, replacement time, and what it takes to program a replacement. Modules marked dealer / factory tool won't work after a part swap alone — budget for programming.
⚠️ Power seat memory and heating/cooling; multiple modules (one per seat).
Aftermarket tool coverage varies by software version and vehicle build — treat "aftermarket tool" rows as "usually possible" and verify against your tool maker's coverage list before promising a customer. Spot a wrong location or hour? Tell us — corrections ship fast here.
Volvo Car USA, LLC (Volvo Car) is recalling certain 2020-2021 S90, 2020-2022 S60, V60, XC60, XC90, and 2022 V90 plug-in hybrid vehicles. The high-voltage battery may experience a short circuit within the battery module when the battery is fully charged and the vehicle is parked.
Consequence: A short circuit in a high-voltage battery increases the risk of a fire.
Remedy: Owners are advised not to charge their vehicles until the remedy has been completed. Dealers will inspect and replace the high-voltage battery module as necessary. In addition, dealers will update the software to monitor the battery. All repairs will be performed free of charge. Owner notification letters were mailed May 28, 2025. Owners may contact Volvo Car's customer service at 1-800-458-1552. Volvo Car's number for this recall is R10312.
SERVICE BRAKES, HYDRAULIC:ANTILOCK/TRACTION CONTROL/ELECTRONIC LIMITED SLIP · 21V716000
2021-09-15
Volvo Car USA, LLC (Volvo Car) is recalling certain 2021 S90L, 2020-2021 XC60, and XC90 vehicles. An improperly welded rotor and shaft may separate within the integrated brake system.
Consequence: Separation of the rotor and shaft may cause a reduction in braking assistance and a loss of the Antilock Brake System (ABS) and Electronic Stability Control (ESC), increasing the risk of a crash.
Remedy: Dealers will replace the hydraulic unit, free of charge. Owner notification letters were mailed October 22, 2021. Owners may contact Volvo Car customer service at 1-888-458-1552. Volvo Car's number for this recall is R10120.
Performance
Horsepower
250hp
Torque
258lb-ft
0–60 mph
6.3sec
Quarter mile
14.8sec
Top speed
130mph
Fuel economy (EPA)
City
28mpg
Highway
32mpg
Combined
30mpg
Fuel
Premium Gasoline
Capability & size
Curb weight
3,945lb
EPA class
Midsize Cars
Wiper blades
Sedan body style, no rear wiper. Both blades are same length.
Size-standard part numbers — verify your connector type before buying. Rear blades are model-specific; check the package's vehicle list.
Fuel economy figures are EPA data via fueleconomy.gov (median across matching trims). Performance figures are compiled estimates for the 2021 Volvo S90 2.0L I4 Turbo and can vary by trim.
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years.