Parts for your 1991 Nissan Primera-Temperature sensors

1991 Nissan Primera temperature-sensors — what they do and how to look after them

Temperature-sensors are absolutely fitted to the 1991 Nissan Primera (P10). Technical sources including the Nissan Primera P10 Factory Service Manual (1990–1992, EC/ECCS and EL sections), the Haynes Nissan Primera Petrol & Diesel 1990–1999 manual, and Nissan FAST parts listings confirm multiple temperature-sensors on GA16DE, SR20DE and CD20 engines. These include an engine coolant temperature (ECT) sensor for the ECU, a separate sender for the dash gauge, and an intake air temperature (IAT) sensor (often integrated with the air flow meter on many models). Depending on market and spec, radiator fan control is handled by the ECU via the ECT signal, and/or a dedicated thermo switch.

The ECT sensor is a key player. It tells the ECU how warm the engine is so it can sort cold-start enrichment, ignition timing, idle speed and fan operation. The dash sender drives the temperature gauge under the bonnet’s watch, while the IAT helps tweak fuel delivery as intake temps change on hot Aussie or Kiwi days. When an ECT goes out of range, expect hard cold starts, rough idle, sooty plugs, poor fuel economy, or fans stuck on/off. A lazy gauge sender can mislead with readings that wander or sit dead.

There’s no fixed replacement interval for temperature-sensors, but they should be checked during routine servicing, especially if there are starting issues, high fuel use, or odd gauge behaviour. Good practice includes:

• Inspect connectors and wiring at the thermostat housing/water outlet for corrosion or broken tabs.
• Test the ECT with a multimeter against the service manual chart (typical Nissan NTC values are roughly 2–3 kΩ at 20°C and 200–300 Ω at 80–90°C