Here's how it can happen:
1. Exhaust Heat: The exhaust system generates a significant amount of heat when the engine is running. The heat plate, being in close proximity to the exhaust, will be exposed to this intense heat as well.
2. Thermal Expansion: As the heat plate absorbs heat from the exhaust, it will expand. Metals tend to expand when heated, and this expansion can cause the heat plate to change shape or buckle slightly.
3. Knocking Sound: If the heat plate makes contact with any surrounding components or surfaces due to its expansion, it can create a knocking or rattling sound. The vibration caused by the contact between the heat plate and other parts of the vehicle can produce this knocking noise.
4. Resonance: In some cases, the design and shape of the heat plate, along with the vibrations from the exhaust system, can create a resonant frequency. This means that the vibrations amplify and become more noticeable, resulting in a pronounced knocking sound.
It's worth noting that knocking sounds emanating from the exhaust area can have various other causes besides a heat plate, such as issues with the exhaust system itself, the engine, or related components. A qualified mechanic should inspect the vehicle and determine the exact source of the knocking sound to ensure proper repair or maintenance.
