Parts for your 2009 Mitsubishi Outlander-Exhaust gasket

2009 Mitsubishi Outlander exhaust gasket — what it does and when to replace it

Yes, the 2009 Mitsubishi Outlander uses exhaust gaskets. This is confirmed by Mitsubishi Motors’ Outlander CW-series workshop manual (2007–2012, Group 15: Exhaust), which shows gaskets at the manifold-to-head and pipe joints, and by the Mitsubishi ASA electronic parts catalogue listing multiple exhaust gaskets and crush rings for CW5W/CW6W models (2.4L 4B12 and 3.0L 6B31). Major aftermarket catalogues (Fel-Pro, Mahle, Walker) also list manifold and flange/donut gaskets for this exact model year, sealing the deal that exhaust gaskets are fitted and serviceable items.

On a 2009 Outlander, exhaust gaskets sit between key joints — typically the exhaust manifold and cylinder head, the front pipe/catalyst connections (often a spring-loaded “donut” gasket), and rear flange joins. Their job is simple but crucial: keep hot exhaust gases inside the pipes, stop fumes sneaking into the cabin, quieten the note, and let the oxygen sensors read cleanly so the engine management can trim fuel properly.

Because they live in a hot, corrosive spot under the car, these gaskets can eventually harden, crack or crush down. Common telltales include a ticking or puffing noise on cold start, a whiff of exhaust near the firewall or underbody, black sooty marks around a flange, or a faint hiss under load. Sometimes the dash will light up with a catalyst or fuel-trim code if a leak is ahead of an O2 sensor.

For servicing, the rule of thumb is replace, don’t reuse. Once a joint is apart — whether for a manifold, cat, or muffler job — a fresh gasket is cheap insurance. On the Outlander, it’s smart to have new spring bolts and the front-pipe donut on hand, as those fasteners cop the brunt of heat and road splash. Fit quality gaskets (MLS or graphite/metal ring as specified), clean the mating faces with a plastic scraper or Scotch-Brite, align everything without prying, and torque to the workshop spec in stages. After the first proper heat cycle, a quick recheck of accessible flange fasteners helps keep things tight.

• Replace on disturbance or if leaking — there’s no fixed kilometre interval.
• Use high-temp anti-seize sparingly on studs/nuts