To understand a pop from the exhaust when slowing down, compare it under normal, safe conditions: cold versus warm, idle versus steady speed, and light versus higher load. Note whether it happens after a gear change, on overrun, or only when the engine is cold. Change one condition at a time so the result stays useful.
Do not create a risky test just to reproduce it. Check for exhaust leaks and recent intake or exhaust work; do not touch hot components.
Quick educational note
For information, not a diagnosis or repair instruction. Vehicle-specific checks are still required. Consult the manufacturer's guidance and a qualified technician.
How to use this information
This article explains general principles and does not establish what is wrong with your vehicle. Read the content limitations.