Parts for your 2012 Nissan Pulsar-Radiator cap

2012 Nissan Pulsar radiator-cap

Referencing Nissan’s factory service literature for the Pulsar/Sentra platform (2012–2013, Cooling System section), the vehicle is designed with a pressure-type radiator-cap as part of its closed cooling system. The manuals describe cap inspection and specify an opening (relief) pressure around 0.9 bar (≈90 kPa), confirming a radiator-cap is indeed used. On many 2012 Pulsar variants, the pressure cap is located on a remote filler neck or the pressurised reservoir (degas bottle), rather than on the radiator itself—so the system still relies on a proper radiator-cap, just not always on the radiator top tank.

This radiator-cap does more than just seal the top. It holds pressure so coolant can run hotter without boiling, which helps the Pulsar keep its cool on summer road trips and long Kiwi hill climbs. When pressure builds beyond the cap’s rating, it safely vents a bit of coolant to the overflow bottle, as the engine cools, a small vacuum valve lets coolant return so the system stays full and bubble-free. The cap is also a key service point for bleeding and topping up, especially on cars with a remote filler.

For a 2012 Nissan Pulsar, it’s smart to check the radiator-cap at each service (about every 10,000–15,000 km or 12 months). Look for a cracked or hardened rubber seal, bent tangs, corrosion on the neck, or any gunk that could stop it sealing. If there’s a cooling complaint, a workshop can test the opening pressure with a cap tester, if it opens too low, replace it. Stick to a cap that meets Nissan’s specified rating (typically 0.9 bar), whether genuine or a quality equivalent.

Common red flags of a tired cap include slow coolant loss, the overflow bottle staying too full or bone dry, random overheating at highway speeds, or a top hose that collapses after cool-down. Always open the cap only when the engine is stone cold. If there’s a two-step neck, pause at the first stop to bleed any residual pressure. When refitting, make sure the sealing surfaces are clean and the cap is fully seated. After any cap replacement, refill with the correct Nissan blue long-life coolant mix, run the heater, and bleed out air so the Pulsar’s cooling system does its best work.

Popular questions about 2012 Nissan Pulsar radiator-cap

Where is the radiator-cap on a 2012 Pulsar?
On most 2012 Pulsars, the pressure cap sits on a remote filler neck or the pressurised reservoir (degas bottle), not directly on the radiator. Look near the upper radiator hose area or on the translucent coolant tank.

What pressure cap does a 2012 Pulsar use?
Most Australian and New Zealand 2012 Pulsar models specify a cap around 0.9 bar (≈90–100 kPa). Always confirm against the cap label or the cooling system section of the Nissan service manual for the exact engine variant.

How often should the radiator-cap be replaced?
Have it inspected annually and pressure-tested if there are cooling symptoms. Many owners replace the cap preventatively every 5 years or when doing a major coolant service if the test results are borderline.