What Causes the Metallic Sound from the Exhaust Pipe?
2 Answers
The metallic sound from the exhaust pipe can be caused by reasons such as an overly lean air-fuel mixture. Below are the specific causes of the metallic sound from the exhaust pipe: 1. Overly Lean Air-Fuel Mixture: This usually occurs when the engine is at medium to high speed, causing backfiring in the exhaust pipe. The issue may improve or disappear after accelerating. This happens because the spark energy is insufficient to ignite the overly lean mixture, which then enters the exhaust pipe and combusts, causing backfiring. Generally, the problem can be resolved by cleaning the fuel injectors and adjusting the fuel injection quantity. 2. Exhaust Pipe Backfiring: As the name suggests, exhaust pipe backfiring refers to the explosive sound produced when unburned combustible mixture reignites inside the exhaust pipe, often accompanied by sparks. This is commonly known as exhaust pipe backfiring. 3. Faulty Connecting Components: The exhaust pipe is connected to the engine via a flexible joint, which may become damaged after prolonged use. Additionally, the exhaust pipe is secured to the chassis by several rubber rings. It's advisable to check if these rubber rings are damaged or have aged. Lastly, there are seals between the exhaust pipe and the flexible joint, as well as between the flexible joint and the engine. These seals should also be inspected for any damage.
A few days ago, my car's exhaust pipe started rattling, sounding like metal fragments vibrating inside, which made me quite nervous. It's probably because the exhaust pipe clamps have loosened or rusted and broken, as I often drive on rough roads with lots of bumps that can wear out the joints. Another possibility is that the internal baffle of the muffler has cracked, causing parts to fall off and hit the metal pipe walls. This noise becomes even more noticeable at high speeds, sounding like a tractor—not only annoying but also risking sudden detachment that could scrape the undercarriage. I immediately drove to the repair shop for a check, and it turned out the hanger screws were loose. The mechanic tightened them, and the problem was fixed. So, I suggest you don’t delay—get your exhaust pipe mounting points checked at a shop to avoid bigger issues.