If the timing chain breaks while the engine is running, this can cause the pistons to collide with the valves with disastrous consequences. This will often damage the engine beyond repair.
Since this is the case, many newer car engines are designed to mitigate this. This includes most cars made since the early 1990's.
On an interference engine it can damage the valves, heads, and pistons.
Your car has the 1NZ-FE engine featuring VVT-i (variable valve timing with intelligence). This is a non-interference engine, with a timing chain. While a broken chain could cause damage to your engine, it is less likely to cause damage on a non-interference engine, and if the chain is damaged (but not completely snapped) you will often know it because it will make a lot of noise (stop driving it at that point and get the chain replaced). The chain is generally considered good for 250,000 miles unless it begins making noise.
A timing chain, that needs to be replaced, can cause your engine to run rough and lose power. A broken timing chain can cause significant engine damage.
The 1999 Ford Taurus does not have a timing belt. It has a chain that requires no maintenance.
If the timing belt on a 1.6 Astra breaks, it can damage the engine. It is more likely to damage the engine if it is a timing chain, though. A timing chain is made of metal and a timing belt is made of a heavy duty rubber.
With a broken chain the engine won't run at all.
It has a chain and the chances of it breaking are slim to none. It is designed to last the life of the engine.
Timing chain noise is most commonly coming from a loose chain. The tensioner could be loose or broken or the chain could be stretched. If the chain slips or breaks before you fix it, then not only will the engine stop running but you could cause serious damage.
Usually that is a sign of a broken timing belt or timing chain.
not gospel but 4.0 sohc engine is an interference major damage if timing chain or timing chain tensioner breaks
its a chain, and a non-interference (free spinning) engine. which means, in case of a timing chain failure, the valves will clear the pistons and there will be no engine damage
One way to tell if the timing chain is broken on your Nissan Altima is to see if it will start. If it starts, it is not the timing chain. You can also remove the distributor cap, have someone step on the gas while you watch the engine. If the rotor moves, it is not the timing chain.