You would need to pull one of the covers off and look at its physical condition.
It is probably not a belt, but rather a chain
The 2.7 liter 4 cylinder has a timing CHAIN , the 3.4 liter V6 has a timing BELT on the 1999 Toyota 4 Runner
Your 1999 Chevy blazer doesn't have a timing belt.
A computer diagnostic test will show a timing belt problem for a 1999 Mazda 626. If there is a problem with the belt, diagnostics will determine if it needs to be repaired or replaced.
The timing belt needs to be replaced about every 100k miles. Actually the recommended interval is 105,000 miles. You also replace the tensioner and idler pulley at this time
90k
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.
Very Carefully Very Carefully
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.
it depends. is it a chained-like timing belt or a continuous piece of fabric-like timing belt?
It has a timing chain which will last the life of the engine.