Does the timing chain need to be replaced?

[LeGrant]

The timing chain needs to be replaced, but not on a regular basis. The timing chain is lubricated by engine oil. If the engine oil is not changed for a long time or the oil quality is poor, it can easily increase the friction between the timing chain and the sprocket, which will reduce the lifespan of the timing chain. However, even when the timing chain reaches the end of its lifespan, it won't break immediately but will gradually stretch. The consequence of stretching could be valve interference, leading to unstable engine operation and poor acceleration, or it might skip teeth, causing engine failure. Generally, it's recommended to inspect the timing chain after about seven to eight years of driving or around 100,000 kilometers, while the replacement cycle is typically around 150,000 to 200,000 kilometers.

[VanLucille]

My old Passat had its timing chain stretched at 180,000 kilometers, making a rattling noise like a tractor during cold starts. The mechanic said while chains do last longer than belts nowadays, poor oil quality or extended maintenance intervals can accelerate wear. If you hear metallic scraping sounds from the front of the engine, chain skipping could bend valves and damage pistons, costing 20,000-30,000 yuan to repair. Now I have the mechanic check the chain tensioner's extension with a diagnostic tool every 50,000 km - replacement is needed if it exceeds limits. For older cars, frequent inspections are wise; a complete chain replacement costs just 3,000-4,000 yuan, far cheaper than major engine repairs.

[McPaislee]

I've driven for over 20 years and replaced the timing chain more than a dozen times. Although it looks like metal, the tensioner and guides are made of plastic and will degrade over time. Manufacturers claim it's maintenance-free for life, but that's just theoretical—actual lifespan depends on driving habits. Cars frequently used for short trips need special attention, as shutting off the engine before the oil fully warms up can lead to sludge buildup and poor lubrication. Last week, while helping a neighbor inspect their car, I found the chain guide had shattered into pieces, with small fragments nearly clogging the oil pump—a disaster narrowly avoided. I recommend removing the oil pan for inspection every 100,000 km and cleaning the oil pump screen while you're at it.

[VeraFitz]

Previously worked on a Cruze where the owner reported sudden increase in fuel consumption and lack of power during acceleration. Using an oscilloscope, we detected abnormal waveform from the crankshaft position sensor. Upon disassembly, found the timing chain had stretched by 7 degrees. Actually, during routine maintenance, you can clearly compare new vs old chains by shining a flashlight through the chain cover inspection hole: new chain links show uniform gaps between segments, while worn ones exhibit uneven spacing. Some German cars may illuminate a wrench warning light on the dashboard when there's chain issues - don't wait until it skips teeth to address it. Modern extended-life chains with roller-pin construction can last up to 250,000 km, though taxis are an exception.