Parts for your 2019 Subaru Impreza-Oil cap

2019 Subaru Impreza Oil Cap — What it does and when to replace it

Yes, the 2019 Subaru Impreza absolutely uses an engine oil filler cap. Technical documentation such as the 2019 Subaru Impreza Owner’s Manual (engine compartment layout) and the Subaru Service Manual for the FB20 engine identify and label the “Engine oil filler cap” on the rocker cover under the bonnet. It’s a standard, must-have part on the petrol FB-series engine fitted to this model.

The oil cap’s job is simple but critical: it seals the top of the engine so oil can’t splash out, keeps dust and moisture from getting in, and helps maintain correct crankcase ventilation. If it’s loose, cracked, or missing, owners may notice oil mist around the cover, a hot oil smell, or a messy engine bay. In worse cases, unmetered air can upset crankcase pressure and cause rough running. That’s why Subaru’s service literature calls for checking the cap and surrounding area whenever the engine oil is serviced.

As part of regular servicing, the cap should be removed and refitted with each oil change. Inspect the cap’s rubber gasket/O-ring for flattening, cracks, or hardening, replace it if it doesn’t feel supple. Wipe the sealing surface on the rocker cover, make sure no grit is present, and refit the cap hand-tight to a firm stop—no tools needed. A light film of clean oil on the O-ring helps it seat without grabbing. Only open the cap when the engine is cool to avoid burns or splashing oil vapour.

When it’s time to replace, choose a genuine Subaru cap or a high-quality equivalent that’s stated to fit the 2019 Impreza’s FB20 engine. Cheap, ill-fitting caps can seep or work loose. Typical signs it’s due for replacement include a perished gasket, hairline cracks in the plastic, persistent weeping around the cap, or a cap that no longer tightens positively.

• Signs the oil cap needs attention: oil smell after drives, damp oil around the cap, brittle or flattened seal, cap difficult to remove or won’t snug up.
• Quick check each service: clean the seat, inspect the O-ring, lightly oil the seal, and refit hand-tight.

Referencing the Subaru Owner’s Manual and the 2019MY Service Manual (Lubrication section) backs up these simple checks, which help keep the Impreza tidy, leak-free, and breathing properly between oil changes.

FAQs

Where is the oil cap on a 2019 Subaru Impreza?
It sits on top of the engine under the bonnet, on the rocker/valve cover, clearly marked “OIL”. It’s designed for easy access during routine oil checks and changes.

Look for a circular plastic cap, it turns anticlockwise to remove and clockwise to refit, hand-tight.

What replacement oil cap or seal fits the 2019 Impreza?
Use a genuine Subaru oil filler cap or a reputable aftermarket cap specified for the FB20 engine used in the 2019 Impreza. The cap includes a rubber gasket/O-ring—replace the whole cap or the seal if it’s worn.

Stick with quality parts so the seal stays tight and the cap doesn’t back off with vibration.

Is it safe to drive if the oil cap is missing or damaged?
Not recommended. Oil can spray out, contaminants can get in, and crankcase ventilation can be upset, leading to smells, a mess, and possible drivability issues.

If the cap is lost or cracked, sort it before driving. At most, move the vehicle a very short distance and replace the cap immediately.