4 Symptoms Of A Bad Timing Belt To Watch Out For: Capitol Subaru Car Care

January 27, 2020

While most of the very latest Subaru models feature a permanent metal timing chain, older Subaru models and the ultra-high-performance Subaru WRX STI feature a rubberized timing belt. Just like rubber accessory belts under the hood, the timing belt may stretch and crack over time. And since modern Subaru engines are interference engines, that means that a broken timing belt could cause severe damage to the engine! That's why it's crucial to get the timing belt on your Subaru changed before it fails. Here are four signs that the timing belt on your car may need to be replaced.

If you have a Subaru Outback, Forester or other non-STI vehicle from the 2014 model year or newer, your car is equipped with a timing chain that doesn't need regular maintenance. However, if your Subaru model is older than that, you may have a timing belt under the hood. That means you'll want to pay close attention to the information below.

4. Engine Misfiring

The role of the timing belt is to synchronize the engine's moving valves and pistons. When the timing system is working properly, the valves open and close at the ideal moment in the pistons' travel. If the timing belt became stretched out or misaligned, the exhaust or intake valves could remain open when the spark plug fires and the combustion process begins. This can allow combustion to take place in the exhaust system or the intake manifold, known as a misfire. A misfire will cause your engine to run roughly, inefficiently and could lead to damage. A misfiring engine should be evaluated by a certified technician right away.

3. Engine Stalls And May Not Start

If the timing of the engine comes far enough out of whack, it may even cause the engine to stall. If the timing belt breaks completely, there'll be no connection between the engine's driveshaft and camshaft(s) and the engine will stall and won't be able to start. The timing system operates the engine valves -- without it, the engine simply can't get going. If your timing belt snapped, get a tow to the Capitol Subaru service center so that our factory-certified technicians can make a high-quality repair.

2. Engine Ticking Noise (Engine Knock)

Engine knock is a phenomenon where the air/fuel mixture inside the cylinder doesn't detonate in a single, smooth explosion. Instead, parts of the air/fuel mixture combust prematurely. The result is a tell-tale ticking noise from the engine. It'll also cause your car to lose power and fuel efficiency.

If your engine timing system is just slightly off, but not so bad as to cause the engine to stall or misfire, engine knock is a likely symptom. You may need to have the belt tensioners adjusted, or simply have the belt itself replaced.

1. Recommended Maintenance Interval Reached

Of course, the most important factor to keep an eye on when it comes to your timing belt is the odometer. Subaru has engineered and tested its factory timing belts for a particular lifetime, after which it's time to get it replaced. For example, the engine in the 2012 Subaru Outback features a timing belt. According to the manufacturer's recommended maintenance schedule, this timing belt should be regularly inspected every 30,000 miles. That way, a certified Subaru technician can look for signs of wear and recommend replacement if necessary. Beyond this, Subaru recommends the belt be replaced regardless of condition at 105,000 miles.