What is an interference engine and is my Toyota engine an interference engine? Why should I care?
An interference engine is one in which the valves and pistons can touch if the cams and crank are not kept in correct timing by the timing belt or chain. Most (not all) Toyota passenger car engines are free-running (non-interference engines). This means that if your timing belt breaks, then all that will happen is your engine will not run anymore until the belt is replaced. In an interference engine, piston-to-valve contact will cause very serious damage to the engine if the timing belt breaks. To see if your engine is an interference engine or not, look it up in the following brochure: http://www.gates.com/downloads/download_common.cfm?file=TBR05.pdf&folder=brochure An asterisk opposite your engine means it is an interference engine.
