Parts for your 2017 Subaru Forester-Manifold gasket

2017 Subaru Forester manifold gasket: what it does and when to replace it

Yes, a manifold gasket is fitted to the 2017 Subaru Forester. Technical references including the Subaru 2017MY Forester Service Manual (Engine: Intake and Exhaust sections) and the Subaru Electronic Parts Catalogue specify both intake manifold gaskets (between the manifold and cylinder heads) and exhaust manifold gaskets (between the exhaust manifold/headers and the heads). This applies across the FB20/FB25 petrol engines and the FA20 turbo models, so “manifold-gasket” is absolutely relevant to this vehicle.

On this Forester, manifold gaskets seal hot gases and intake vacuum where metal parts meet. The intake manifold gasket keeps unmetered air out, so the engine management can meter fuel properly. The exhaust manifold gasket keeps combustion gases contained and, on turbo models, maintains energy to spool the turbo efficiently. Because these joints see heat cycling, vibration and clamping loads, the gaskets are engineered crush materials or multi-layer steel that conform to minor surface imperfections to maintain a tight seal.

When a gasket starts to fail, owners might notice rough idle, a ticking noise on cold start, or that tell-tale whiff of exhaust under the bonnet. An intake leak can push fuel trims lean and light the MIL with codes like P0171. An exhaust leak can leave sooty marks around the flange, trigger oxygen-sensor drama, and on the XT turbo, sap boost response.

• Common signs: hissing or ticking noises, rough idle, reduced power, fuel economy drop, exhaust smell in cabin, visible soot at the joint.
• When to replace: whenever the manifold is removed, or any time a leak is suspected. There’s no fixed kilometre interval.
• Good practice: use new gaskets every refit, avoid sealants unless the Subaru procedure specifies them, follow the factory torque specs and sequence.

For servicing, it’s smart to inspect these joints during major work (around the 100,000 km mark or when doing plugs/PCV/carbon cleaning). Cleaning the mating faces, checking manifolds for warp, and using quality OEM-equivalent gaskets keeps things drama-free. On turbo Foresters, also renew the turbo-to-manifold and up-pipe/downpipe metal gaskets if disturbed, and check the spring bolts and studs for tension and corrosion.

DIYers can tackle intake gaskets with patience and the right torque pattern, exhaust work may need penetrating oil, heat and fresh hardware. After replacement, a quick smoke test or soapy-water check (for exhaust, listen on cold start) helps confirm a perfect seal so the Forester runs sweet as.

Popular questions

Does the 2017 Subaru Forester have intake and exhaust manifold gaskets?
Yes. Subaru’s 2017MY Forester Service Manual and Electronic Parts Catalogue list both intake manifold gaskets and exhaust manifold gaskets for FB and FA engines. They’re standard sealing components designed to keep the intake airtight and the exhaust leak-free.

How often should manifold gaskets be replaced on a 2017 Forester?
There’s no scheduled interval. Replace them any time the manifold is removed, or if there are leak symptoms like hissing, ticking, soot marks, or fuel trim issues. During major services, inspecting these joints is a sensible preventative step.

What are the symptoms of a bad manifold gasket on this model?
Expect rough idle, lean codes, poor fuel economy, or a sharp tick on cold start for exhaust leaks. Intake leaks can cause a hiss and unstable idle. Turbo models may feel lazier to spool if there’s a pre-turbo exhaust leak.