How to Quiet a Car Engine
- 1). Install the sound-deadening material if your engine is new and performing properly and you just want to reduce the level of noise. Available online or in auto parts stores, this material usually consists of foam and is sometimes coated with heat-absorbing aluminum or polyurethane. It can be applied to the engine bay, usually with an adhesive backing. Pay particular attention to covering the firewall, the partition separating the engine from the passenger compartment.
- 2). Tighten any nuts and bolts that may have come loose and can cause your engine to rattle. This reduces noise and engine vibrations. Make sure the bolts are torqued to proper specifications by using the torque wrench.
- 3). Perform a periodic "tuneup" on your vehicle to help reduce noise and prevent excessive engine wear. Replace the filters, fluids and spark plugs and adjust the timing of your engine. Have the work performed by your mechanic if you don't feel comfortable doing it.
- 4). Switch to premium fuel if your vehicle is making a pinging or knocking sound, especially when accelerating or climbing up hill. Some higher-performance vehicles require high-octane gasoline, so you might hear less noise and maximize engine performance if you start using it. Consult your owner’s manual for the required octane for your vehicle.
- 5). Make sure your oil level is up to the "full" mark on the oil dipstick. Oil reduces friction, so it may help decrease noise.
- 6). Lubricate moving parts. Screeching sounds coming from the engine belts may be lessened by applying belt dressing or by replacing them, depending on their condition. Also, check the radiator's condition and make sure it has enough coolant if your radiator fan keeps turning on.
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