The Most Common Causes of Engine Rattling

We are going to try to keep this simple. We could go in-depth on what happens inside the engine that causes a rattling noise but to you, that probably isn’t very important. You want to know what to do about this noise your car started making! An engine is made up of many small parts that move at very high speeds while you’re driving. If any of these parts develop excessive wear they will move around and cause a rattle. 

How to Fix a Rattling Sound Coming from the Engine

Some engines have adjustments that can be made to compensate for this wear, but many don’t. The most common adjustment an engine might have is adjustable valve clearance. In order for your engine to run smoothly and at top performance, the valves must open and close at exactly the right time. If they’re loose they won’t open or close all the way. This can cause a rattling or ticking sound. 

There are a number of other parts in the engine that can wear and cause a rattle including the pistons, connecting rods, hydraulic lifters, and bearings. 

Engine Rattling Culprits: The Timing Chain and Timing Belt

One other internal engine part that can wear and cause a rattle is the timing chain. Your car either has a timing chain or timing belt. Timing belt replacement should be done at regular intervals based on the manufacturer’s recommendation. If the timing belt and related components are replaced at the recommended intervals, you should never hear any noise from the timing belt.

The timing chain, on the other hand, does not have a recommended service interval and is only replaced when required. The timing chain will require replacement if it starts to make noise or there are fault codes related to it. The noise from a timing chain is often heard on startup, but as it gets worse you will hear it while driving too.

It Might Not Be Your Engine Rattling After All…

The rattling noise might not be inside your engine! A rattle when the engine is running can also be caused by a failing belt tensioner or idler, or something inside your exhaust. The last thing we are going to talk about is heat shields. All cars have thin metal plates either between the body of the car and the exhaust or secured to the exhaust. These shields dissipate the heat so the exhaust does not damage the car. These heat shields can also cause a rattling noise as they deteriorate.

Are you in the Twin Cities and need a trusted mechanic to help your engine stop rattling? We’d love to help. Give us a call, email us, or stop into our southeast Minneapolis location to speak with a technician today.