When diagnosing a suspension problem in your Nissan Primera, start by inspecting the suspension components for any signs of damage or wear, such as leaking shocks or worn bushings. Check for abnormal tire wear, noise, or uneven ride height. Perform a visual inspection of the suspension system and conduct a bounce test by pushing down on each corner of the vehicle to check for excessive bouncing or instability. If the issue persists, it is advisable to consult the automotive repair manual or seek professional assistance for a more detailed diagnosis and repair.