What is the black part under the car bumper?

[LandonMarie]

The plastic panel below the bumper is called a deflector. Here are the details: To reduce the lift generated when a car is driving at high speeds, car designers not only improved the exterior shape of the car but also installed a downward-sloping connecting panel under the front bumper. This connecting panel is integrated with the front skirt of the car body, with a suitable air intake in the middle to increase airflow and reduce the air pressure under the car. Additional information: Bumper protection precautions: 1. Use corner indicator posts to determine the position of the bumper. The vertical markers at the corners of the bumper are indicator posts that help accurately confirm the position of the bumper corners, prevent bumper damage, and improve driving skills. 2. Installing corner rubber can reduce bumper damage. The corners of the bumper are the most vulnerable parts of the car's exterior and are prone to scratches, especially for those with poor driving skills. Corner rubber protects these areas, is easy to install, and can be directly attached to the corners of the bumper to minimize damage.

[SanMax]

I used to notice this black part while driving. It's actually called a bumper underguard, mostly made of plastic and installed beneath the bumper. Its main function is to protect the car's chassis from scratches caused by stones, puddles, or uneven roads, especially reducing water splashes on rainy days. It also helps improve the car's airflow, making high-speed driving more stable and slightly boosting fuel efficiency. I recommend checking it regularly as it tends to accumulate dust or mud. Just use a soft brush and mild cleaner for cleaning. If it's cracked or severely worn, replacing it at a repair shop isn't expensive, and parts are easily available for most models. Overall, this small yet practical and inconspicuous component significantly enhances the car's durability.

[Ezekiel]

From a design perspective, that blackened area under the bumper is actually a standard plastic underguard. Factories choose black because it's durable, cost-effective, and dirt-resistant. The lightweight plastic material helps reduce vehicle weight and improve fuel economy, while also absorbing minor impacts like parking scrapes. Don't underestimate it - this component prevents curb damage to the bodywork and protects the intake system from water ingress. I recommend checking your specific model, as some newer versions even feature soft rubber edging to minimize noise. Cleaning is straightforward (just avoid harsh chemicals to prevent fading). Periodically inspect for looseness or cracks to avoid worse damage during underbody impacts - timely replacement saves money long-term.

[StHeidi]

Don't overlook this black skid plate. Once, excessive mud accumulation on my car nearly affected the underbody heat dissipation. Made of plastic, it protects components near the engine bay from stone impacts. Cleaning is simple—I usually wipe off dirt with a damp cloth or neutral car wash soap. If exposed long-term, the black color may fade to gray; try UV-protectant sprays for maintenance. If scratched, just replace it at a repair shop—matching panels for your car model cost very little. Overall, it serves as a safety barrier preventing road debris from invading the chassis.