P0128 on a Nissan: Causes, Fixes & Repair Cost
🟠 Moderate severity · drivable
Safe to drive, but the engine running cool hurts fuel economy and heater output, so plan the thermostat repair soon.
What P0128 means on a Nissan
On a Nissan, P0128 means the engine computer has detected that the engine isn't reaching its normal operating temperature in the expected time. A thermostat stuck open is the usual cause on Nissans like the Altima and Rogue, and on some engines the thermostat housing also holds the temperature sensor.
Is P0128 common on Nissans?
P0128 is a common code on higher-mileage Nissans, especially the Altima, Sentra, Rogue, and Versa. The thermostat is the first part to check, and the repair is one of the cheaper cooling-system jobs on these cars.
Commonly reported on: Altima, Sentra, Rogue, Versa.
Symptoms
- Check engine light is on
- Temperature gauge reads below normal
- Heater blows lukewarm air
- Fuel economy drops in cold weather
Common causes
- most common: Thermostat stuck open
- common: Low coolant level
- common: Coolant leak at a hose or the housing
- less common: Faulty coolant temperature sensor
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Top up the coolant and check for leaks | Yes | $10–30 |
| Replace the thermostat | Yes | $40–120 |
| Replace a faulty coolant temperature sensor | Yes | $40–110 |
Frequently asked questions
Other common Nissan codes
P0128 on other brands
Looking for the full (non-brand-specific) guide? See the P0128 code page →
Browse all Nissan codes: Nissan hub →
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.