Parts for your 2008 Honda Stream-Oil cap

2008 Honda Stream oil cap: what it does and how to look after it

Yes, the 2008 Honda Stream uses an oil filler cap. Technical sources including the Honda owner’s manual and Honda service/workshop manuals show an oil filler cap on the cam cover for both R18A 1.8‑litre and R20A 2.0‑litre petrol engines. Honda’s electronic parts catalog for RN6–RN9 variants lists an “Oil Filler Cap” assembly (commonly 15610‑RNA‑A01 on R18A models), confirming it’s a standard, required component.

The oil cap on a 2008 Honda Stream is a small bit of kit that does a big job. It seals the top of the engine where oil is poured in, keeping dust and moisture out and engine oil in. With the Stream’s i‑VTEC engines relying on clean, correctly pressurised oil to keep lifters, camshafts and timing gear happy, a cap that seals properly helps maintain crankcase hygiene and reduces the chance of oil misting around the bay.

During regular servicing, it’s worth giving the cap a quick once‑over. Wipe it clean, check the O‑ring or gasket for hardening, flattening or cracks, and make sure the threads and the cam cover seat are clean. If the rubber seal feels brittle or the cap doesn’t snug down evenly, replace the seal—or the whole cap if it’s warped or the tabs are worn. Honda doesn’t call for special tools here: fit the cap squarely and tighten by hand until it seats, then a small nip—no need to lean on it. Over‑tightening can damage the seal or the cover.

Common signs the oil cap needs attention include a whiff of burnt oil after a drive, a light film of oil around the cap area, or visible perishing of the O‑ring. If the cap goes missing or cracks, don’t drive it “just to the shops”—unfiltered air can be drawn into the engine, and oil can splash out. Grab a genuine cap (or a quality direct‑fit equivalent for RN6–RN9) to ensure the correct seal profile and material. Steer clear of vented or novelty caps, they can upset the engine’s crankcase ventilation and cause idle or emissions gremlins.

As a simple rule, inspect the oil cap at every oil change and replace the O‑ring whenever it looks tired. It’s cheap insurance for a tidy engine bay and a long‑lived i‑VTEC. And yes, only remove the cap with the engine off, letting it cool a bit first—hot oil and steam aren’t friendly.

• Inspect at each service interval.
• Replace if the seal is perished, the cap is cracked, or it won’t seat squarely.
• Use genuine or direct‑fit caps for RN6–RN9 Stream models.

Popular questions about 2008 Honda Stream oil caps

Where is the oil cap on a 2008 Honda Stream?
It’s on top of the engine’s cam (rocker) cover, usually labelled “Engine Oil” and often with an oil can symbol. On the R18A and R20A engines, you’ll spot it towards the front or top centre of the cover for easy access.

What’s the correct replacement oil cap or seal?
For R18A models, the Honda parts catalog commonly lists oil filler cap 15610‑RNA‑A01. The rubber O‑ring is included with most genuine caps. Always match by VIN or engine code (RN6–RN9) to be safe, especially for R20A variants which may use a superseded part number.

Is it safe to drive without the oil cap?
No. Driving without a cap can let dirt in and oil out, risking engine damage and a messy bay. If the cap is missing or cracked, fit a correct replacement before driving.