Peugeot 106 Stalling Reduced Power

Your symptoms do indeed point towards a fuel pressure issue. The check engine light, stalling, and reduced power are classic indicators. The fuel pressure regulator's job is to maintain constant pressure in the fuel rail, ensuring optimal fuel delivery. If it's malfunctioning, the engine won't receive the correct amount of fuel. A faulty regulator could also cause error entry. Did you, by any chance, check the fuel pump relay and fuse?

I did not check the fuel pump relay and fuse specifically. Could a problem there directly impact the fuel pressure regulator's performance, or would it likely manifest in more general fuel delivery issues? How could it be related to the regulator?

A failing fuel pump relay or fuse could mimic regulator issues, but more often, you'd experience complete fuel starvation or significant starting problems. Since you're seeing intermittent stalling and reduced power, the regulator itself is still the prime suspect, especially if this started after the fuel filter change. Considering the price of parts and complexity, I suggest consulting a workshop; it could save you much headache.

I appreciate your advice. You have confirmed my suspicion about the fuel pressure regulator. Following your recommendation, I had it inspected by a workshop. It was indeed the defective fuel pressure regulator, as suspected. The repair cost me 45€.