Parts for your 2012 Subaru Impreza-Exhaust gasket

2012 Subaru Impreza exhaust-gasket: what it does and when to replace it

Yes, the 2012 Subaru Impreza uses exhaust gaskets. Subaru’s factory service information for the 2012 model year (FB20 engine, Engine and Exhaust sections) and the Subaru FAST electronic parts catalogue specify multiple exhaust gaskets: multi‑layer steel manifold-to-cylinder-head gaskets and sealing rings/flange gaskets between exhaust pipe sections. Both sources note these are single‑use items that should be renewed when the joint is disturbed.

On a 2012 Impreza, the exhaust gasket’s job is simple but critical: seal the joins where hot exhaust gases pass from the cylinder head into the manifold and along the front and mid pipes to the muffler. By keeping the system airtight, the gasket helps maintain correct back‑pressure, protects nearby components from heat and fumes, and keeps cabin noise down. When a gasket starts to give up, the car can sound tinny on cold start, smell a bit fumy, and even lose a touch of low‑down torque.

As part of regular servicing, exhaust gaskets don’t have a set replacement interval. Instead, they’re replaced when there’s a leak or whenever that section of the system is removed. That’s why genuine Subaru and OEM-equivalent procedures call for new gaskets at reassembly—once crushed, they don’t reliably reseal. For owners who clock up lots of kilometres or drive in coastal areas, checking the flanges and hardware for corrosion is smart preventative maintenance.

• Common signs of a tired exhaust gasket:
  • Ticking or puffer noise near the manifold on cold start that quietens as it warms
  • Exhaust smell under the bonnet or near the firewall
  • Sooty marks around a flange or join
  • Slight drop in fuel economy or pep

Replacement is straightforward for a workshop: cool the system fully, soak fasteners, remove heat shields, then split the joint and fit a new gasket. Correct alignment and even torque on clean mating surfaces are key. It’s worth using quality gaskets—Subaru genuine or reputable aftermarket MLS/donut types—plus fresh hardware if the studs or springs are crusty. A quick post-job check for leaks (visual and by ear) wraps it up.

For WRX/ STI variants sold alongside the 2012 Impreza, there are additional turbo‑side gaskets (up‑pipe/down‑pipe), and the same rule applies—replace whenever disturbed, following Subaru’s torque specs and sequence.

• Popular questions about 2012 Subaru Impreza exhaust gaskets

What are the symptoms of a leaking exhaust gasket on a 2012 Impreza?
Typical clues include a sharp ticking on cold start from the front of the engine bay, a whiff of exhaust under the bonnet, and black soot around a flange. Drivers may notice a slightly rougher note and a small dip in low‑rpm response. As it worsens, the noise gets louder and the smell more obvious.

Do exhaust gaskets need routine replacement, or only when leaking?
They’re not a timed service item. Replace them when the joint is opened (manifold off, front pipe dropped, etc.) or if a leak is detected. Because they crush to seal, reusing an old gasket often leads to repeat leaks. Best practice is new gasket, clean faces, and correct torque each time.

Is it safe to drive with a blown exhaust gasket?
Short trips may be manageable, but it’s not ideal. Hot gases can heat‑soak nearby components, fumes can creep toward the cabin, and the leak can skew O2 sensor readings upstream, affecting fuel trims. It’s wise to sort it promptly to protect the car and keep it quiet and efficient.