Parts for your 2014 Subaru Impreza-Manifold gasket

2014 Subaru Impreza manifold-gasket: what it does and when to sort it

Based on the Subaru Factory Service Manual for the FB20 engine (MY2014 Impreza, Intake and Exhaust sections) and the Subaru Genuine Parts catalogue for this model year, the 2014 Subaru Impreza is fitted with manifold gaskets — both intake-manifold and exhaust-manifold types. The service manual specifies gasket replacement when manifolds are removed and details torque sequences for reassembly, confirming the manifold-gasket is relevant to this vehicle.

On the 2014 Impreza, the manifold-gasket seals the joins where the intake manifold meets the cylinder heads and where the exhaust manifold (header) bolts to the heads. Intake gaskets keep unmetered air out so the engine doesn’t run lean, while exhaust gaskets keep hot gases in the exhaust stream to protect nearby components and keep noise and emissions in check. When these seals harden, shrink, or get crushed from heat cycles, they can cause rough idle, a check engine light, ticking from the exhaust side, or a whiff of exhaust under the bonnet.

Manifold-gaskets aren’t a routine replacement item on a service schedule, they’re replaced when the manifold is off or when a leak is suspected. For a 2014 car that’s now well into its service life, age, heat, and road grime make gasket condition worth a look during major work like spark plugs, PCV, EGR cleaning, or exhaust work.

• Common symptoms: hissing or whistling (intake leak), high or unstable idle, P0171 lean codes, ticking on cold start (exhaust leak), sulphur/exhaust odour, soot marks at flange joins.
• Good practice: replace gaskets any time a manifold is removed, use OEM or high‑quality equivalents, clean mating faces to bare metal, avoid sealants unless the factory procedure specifies them.

When replacing the intake-manifold gasket on the FB20, label hoses and connectors, check for brittle vacuum lines, and follow the factory bolt sequence and torque spec to prevent warping. For the exhaust side, work on a cold engine, soak fasteners, and inspect studs and nuts for corrosion — replacing hardware as needed. After reassembly, a quick smoke test (intake) or soapy-water check (exhaust, with care) helps confirm a tight seal. Keeping these seals healthy saves fuel, reduces emissions, and keeps the boxer engine running smoothly and quietly kilometre after kilometre.

Popular questions about the 2014 Subaru Impreza manifold-gasket

How long do manifold-gaskets last on a 2014 Impreza?
They often last well over 150,000 km, but age, heat cycles, and previous disassembly can shorten their life. They’re typically replaced when a leak is confirmed or a manifold is removed for other work.

Can a leaking intake manifold-gasket cause engine damage?
It can cause lean running, misfires, and elevated combustion temperatures if ignored. While catastrophic damage is uncommon, prolonged lean operation isn’t good for valves or the catalytic converter, so it’s worth fixing promptly.

Should sealant be used with a new manifold-gasket?
For this model, the factory procedure specifies dry installation for the intake and exhaust manifold-gaskets. Only use sealant where the service manual explicitly calls for it.