the general rule of thumb is at or around 100k miles. this varries with manufacturer, but it is best to always replace no later than 125k
It has a timing belt which must be replaced every 120,000 miles.
The '99 Chevy Prizm has a timing chain, not a timing belt, so it does not need to be replaced.
The 3.0 L V6 has a timing belt that must be were replaced every 90,000 miles. It is not an interference engine. The four-cylinder has a timing chain that requires no maintenance.
It has a timing chain which will last the life of the engine.
This is like asking "when should I have the cylinders reground or the oil pump replaced. A timing chain is not like a timing belt in that it is not subject to 80,000 mile replacement. So, keep your oil changed every 3000 miles and drive on.Good luck !!!
You fail to list what model KIA and what engine. The only 1999 KIA that has a chain is the Sephia with the 1.8L engine. This is an INTERFERENCE engine and as such, if the belt breaks, serious engine damage will occur. The belt must be replaced every 60,000 miles, except California models which is every 100,000 miles.
It is probably not a belt, but rather a chain
It has a belt which must be replaced every 105,000 miles. Warning: This is an interference engine and as such you will have serious engine damage if the belt breaks.
Timing chains are designed to last the life of the engine. They are normally replaced during a complete engine overhaul. Unless the chain becomes noisy no maintenance is required.
Timing chain.
Timing Chain
Timing chain Chain