No , the 1.8 liter 4 cylinder in a 1999 Mazda Protege is not an interference engine
timing chain
2.0 liter
On a 1994 Mazda MX-6 : Both the 2.0 liter four cylinder engine and the 2.5 liter V6 engine have a timing BELT
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
timing BELT
Belt.
Timing Chain
Timing CHAIN ( 2.3 liter 4 cylinder and 3.0 liter V6 engines )
The 3.0 liter and 4.0 liter V6 engines have a timing CHAIN ( The 2.5 liter - 4 cylinder has a timing BELT )
It has a timing belt which must be replaced every 120,000 miles.
Belt