Parts for your 2017 Nissan Pulsar-Oil cap

2017 Nissan Pulsar oil cap — what it does, how to look after it, and when to replace it

Yes, the 2017 Nissan Pulsar definitely uses an oil filler cap. This is confirmed by Nissan’s Owner’s Manual for the 2017 Pulsar (C12 hatch and B17 sedan) in the Do-it-yourself maintenance: Engine oil section, which instructs owners to remove the oil filler cap when topping up oil. The Nissan Service Manual (Engine Mechanical, EM) diagrams for the MR18DE and MR16DDT engines also show the cap on the cam/rocker cover, and Nissan’s genuine parts catalogue lists an Oil Filler Cap (Lubrication group, Cap—Oil Filler) for these engines.

On a 2017 Nissan Pulsar, the oil cap seals the top of the engine’s oil fill neck, keeping the lubricant clean and the crankcase closed so the Positive Crankcase Ventilation (PCV) system can do its job. It stops dust, moisture, and grit from getting into the oil, and prevents oil mist from escaping. It’s a simple bit of kit, but if it cracks, the seal hardens, or it’s left loose, the engine can idle rough, trigger a warning light, or sling oil around the bay.

As part of regular servicing on a 2017 Pulsar, the oil cap deserves a quick once-over. Wipe it clean during oil changes, check the rubber O-ring for flattening or splits, and make sure the threads engage smoothly. It should go on by hand until the seal meets the cover, then a firm nip—no need to reef on it. Cross-threading or overtightening can damage the cam cover and create leaks. If the cap’s missing, cracked, or the seal’s gone hard or swollen, replace it straight away with a correct, closed (non-vented) cap to maintain emissions compliance and proper crankcase ventilation.

Genuine or high-quality aftermarket replacements are inexpensive and fit correctly. If there’s a light oil mist around the filler area, a fuelly smell in the cabin at idle, or a whooshing/whistling from the top of the engine, add an oil cap and seal check to the to-do list. Keeping this small part in good nick helps protect the Pulsar’s MR-series engine and keeps every oil change tidy and drama-free.

• Replace the cap if it’s cracked, warped, or the seal is flattened or brittle.
• Avoid vented “breather” caps, the Pulsar needs a sealed cap for the PCV system.
• Always refit the cap before starting—running without it can cause oil loss and rough running.

References: Nissan Pulsar (C12/B17) Owner’s Manual, Do-it-yourself maintenance: Engine oil, Nissan Service Manual (EM – Engine Mechanical) component layouts, Nissan genuine parts catalogue (Lubrication group, Cap—Oil Filler) for MR18DE/MR16DDT.

FAQs

Where is the oil cap on a 2017 Nissan Pulsar?
On both the MR18DE and MR16DDT engines, the oil filler cap sits on the top of the cam/rocker (valve) cover and is marked “OIL”. Viewed from the front of the car, it’s near the centre on most MR18DE models, and forward-right on the MR16DDT SSS. Always remove it with the engine off and cool.

How do I know if my oil cap or seal needs replacing?
Look for a perished or flattened O-ring, visible cracks, hard-to-start threads, or oil mist around the filler area after driving. A rough idle or whistling from the top of the engine can also point to a poor seal. If in doubt, replace the cap and seal—they’re inexpensive protection.

Can I use any aftermarket oil cap on my Pulsar?
Stick to a cap specified for the MR18DE/MR16DDT. It must be a sealed, non-vented design to suit the Pulsar’s PCV system. Cheap caps can have poor sealing rings or thread fit, a genuine or reputable-brand cap is the safe bet.