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Mazda rx7--timing belt?----2007----125,000 miles

Car makes rattling noise upon ignition. Goes away after warmed up. Some say timing belt needs changing, other say plastic guides? What should I do?

Do you mean RX8 or CX7?

Do rotary engines have timing belts?

I don’t believe a rotary engine has a timing belt. If it is a rotary there are ceramic seals used to seal the rotating piston with the “cylinders”. These seals and the springs to provide tension might be getting old and noisey. It sounds like either something not getting enough oil on start up, or something that when it expands with heat compensates for some loose tolerances due to age.

@flame - you mean a CX-7, right? You don’t have a timing belt, it’s a timing chain. And a rattling noise at start that goes away could be a number of things. You have a turbo 4, right? Are you using premium gas? Has the oil been changed regularly? Who is telling you ‘plastic guides’?

An RX 7 has no need for a timing belt. No camshaft or valves. However, I don’t think they made an RX7 in 2007.