Honda K Series Exhaust Manifold Gasket 18115-PNB-003

Genuine Honda K-Series Exhaust Manifold Gasket (18115-PNB-003) - K20 / K24

An exhaust leak at the manifold is one of those problems that gets worse and costs you the whole time, it ticks or rasps on cold starts, it bleeds away exhaust velocity the engine needs, and it can let fumes into the cabin. This genuine Honda gasket seals the manifold to the head the way the factory did, with multi-layer stainless construction that handles the heat where cheap paper gaskets crush and flake. It's the right part to fix a leak, or to fit whenever the manifold's off for other work.

The Leak You Can Usually Hear

A failing exhaust manifold gasket announces itself. You'll often hear a ticking or raspy exhaust sound, loudest on a cold start and quieting as the engine warms and the metal expands to partially close the gap. You might smell exhaust, and the engine loses a little low-end response because the leak bleeds off exhaust velocity before it reaches the rest of the system.

On a K-series, the original paper-composite style gasket hardens and fails over time and heat cycles, and once it does, the leak only grows. Replacing it with a fresh gasket restores the seal, kills the ticking, and gets back the exhaust flow and the quiet the leak was costing you.

Multi-Layer Stainless, Not Paper

This is a multi-layer stainless steel (MLS) gasket, which is a real upgrade in how it holds up. It resists the extreme cylinder-head and exhaust heat, the turbo heat on boosted cars, and the endless heat cycles that crush and flake a paper-composite gasket. It's rated well past exhaust operating temperatures, so it seals and stays sealed rather than degrading into the next leak.

The fire rings are precision-stamped to match the factory port shape, so it seals cleanly against both the stock manifold and aftermarket headers that keep the OEM flange pattern. Torque it down once and it holds.

Do It While The Manifold's Off

Beyond fixing an active leak, this is the gasket you fit any time the exhaust manifold or header comes off, installing headers, doing a clutch or other work that requires pulling the manifold, or during a rebuild. You never reuse an old exhaust gasket once it's been disturbed; it won't re-seal reliably. It's cheap enough that fresh is the only sensible choice while you're in there, and it saves you pulling the manifold again to chase a leak from a reused gasket.

Fitment

K20 and K24 platforms, including:

2002-2006 Acura RSX
2004-2008 Acura TSX
2003-2007 Honda Accord 2.4L
2002-2011 Honda Civic Si and select trims
2002-2006 Honda CR-V
2003-2011 Honda Element

Part number 18115-PNB-003. Genuine Honda. Confirm against your engine.

Who Should Grab This

This is for anyone with a ticking or raspy exhaust leak at the manifold on a K-series, and for anyone pulling the manifold or header for any reason who should fit a fresh gasket while they're in there. Genuine Honda MLS construction that handles the heat and won't flake like paper, precision fire rings for a clean seal on stock or aftermarket manifolds, and a quick gasket-only install. Seal it up, quiet the tick, and get the exhaust flow back.

Fits: K20/K24, 2002-2006 RSX, 2004-2008 TSX, 2003-2007 Accord 2.4L, 2002-2011 Civic Si and select trims, 2002-2006 CR-V, 2003-2011 Element. Part number: 18115-PNB-003. Type: genuine Honda, multi-layer stainless steel. Fixes: exhaust leak at the manifold (ticking, rasp, lost low-end). Fits: stock manifold or OEM-flange aftermarket headers. Install: gasket only, reuse factory studs/nuts, no tune or cutting.