Parts for your 2009 Subaru Outback-Manifold gasket

2009 Subaru Outback manifold gasket: what it does and when to sort it

Based on Subaru factory service information for Legacy/Outback BP/BL (2005–2009) and the Subaru Genuine Parts Catalogue, the 2009 Subaru Outback uses manifold gaskets. Both the 2.5-litre EJ25 four-cylinder and the H6 variants have intake manifold gaskets between the intake manifold and cylinder heads, and exhaust manifold (header) gaskets between the heads and the exhaust manifold. The workshop manual specifies replacing these gaskets whenever the relevant manifold is removed, confirming the part is absolutely relevant to this model.

On this Outback, the manifold gasket’s job is simple but critical: it seals. The intake manifold gasket keeps unmetered air from sneaking into the engine, so the air–fuel mix stays right and the idle stays smooth. The exhaust manifold gasket keeps hot exhaust gases in the pipes where they belong, so there’s no ticking leaks, fumes, or oxygen sensor misreads. When a gasket starts to fail, owners may notice a rough idle, a hiss or whistle on the intake side, a “lean” fault code (like P0171), or on the exhaust side, a sharp ticking on cold start, a sooty mark near the flange, and a bit more fuel use.

There isn’t a set replacement interval for manifold gaskets on the 2009 Outback