P0121 on Your 2022 Infiniti QX60: The Case File
A P0121 code on your 2022 Infiniti QX60 means the ECM has detected an inconsistent throttle position sensor signal. The voltage is within range but the pattern doesn't match your pedal inputs—our detective has found the first clue pointing to the throttle body system.
The 2022 QX60 is a complete redesign, powered by a 3.5L V6 (VQ35DD) with direct injection producing 295 hp, paired with a new 9-speed automatic. This is a significant change from the previous generation's port-injection VQ35DE engine—the new DI engine is more susceptible to carbon-related throttle issues.
Symptoms
- Check engine light on
- Hesitation during acceleration
- Idle roughness
- Throttle response feels delayed
- Possible reduced power feel
Most Likely Causes
- Carbon buildup on throttle body – The new VQ35DD's direct injection deposits carbon on the throttle plate. This is a departure from the older port-injection QX60. Likelihood: 40%
- ECM software update – First-year redesign; Nissan/Infiniti has released calibration updates for the new 9-speed transmission and throttle integration. Likelihood: 25%
- Throttle body assembly issue – Internal TPS or motor component failure. Likelihood: 20%
- Wiring or connector corrosion – Engine bay heat affecting the throttle body connector. Likelihood: 10%
- Intake air leak – Loose intake duct or gasket. Likelihood: 5%
Repair Costs
- Throttle body cleaning: $100–$180 (shop) / $10–$25 (DIY)
- Throttle body replacement: $350–$600 parts and labor
- ECM update: $100–$200 (dealer)
- Wiring repair: $100–$250
Warranty Coverage
Your 2022 QX60 should be within Infiniti's 4-year/60,000-mile basic warranty and 6-year/70,000-mile powertrain warranty. Both should cover P0121 at no cost. The dealer uses Consult-III+ for diagnostics and can apply Nissan/Infiniti software updates.
How AutoDetective AI Can Help
AutoDetective's AI tracks patterns specific to the redesigned QX60's new VQ35DD engine. Upload your scan data for a free tailored diagnosis.