Why does revs go up and down on zafira?

Revs on a Vauxhall Zafira can fluctuate due to several factors, including issues with the engine management system, problems with the throttle body, or a malfunctioning idle air control valve. Additionally, vacuum leaks or fuel delivery issues can affect engine performance, leading to unstable RPMs. Regular maintenance and diagnostics can help identify and resolve these problems. If the issue persists, consulting a professional mechanic is advised.