Subaru Oxygen Sensor Replacement Cost
Replace upstream or downstream O2 sensor (P0420/P0030 codes).
$200–$450national average
Parts
$80–$280
Labor
0.5–1.5 hrs
DIY-friendly?
Yes (2/5)
Why this fails
Sensors degrade naturally at 80-120k. Failures throw P0420 (cat efficiency) or P0030/P0050 (heater circuit) codes.
What the job involves
- Locate failed sensor (upstream of cat = pre-cat; downstream = rear)
- Penetrating oil + 22mm O2 socket
- Anti-seize on threads (not the tip)
- Clear codes
In-article ad
If you delay this repair
P0420 alone won't strand you, but unburned fuel can damage the catalytic converter ($1,500+ to replace).
Save money
- • NTK or Denso OEM-equivalent is $80-120 vs $250+ at dealer
FAQ
How much does subaru oxygen sensor replacement cost cost in 2026?
Expect $200–$450 at most US shops, parts plus labor.
How long does the job take?
0.5–1.5 labor hours typically.
Can I do this myself?
Yes — DIY difficulty 2/5.
What happens if I delay?
P0420 alone won't strand you, but unburned fuel can damage the catalytic converter ($1,500+ to replace).