Good day, I own a Peugeot 406 & lately fuel spells in my car, more so, I experience hard starting & my fuel economy has dropped. Just few days ago, I was driving home before my vehicle engine went completely off so I had to call a mechanic to tow the vehicle home. A day after, I was told that the fuel pump was bad and that I have to replace it which I did but after that, I still experience hard start. More so, fuel spells inside the car whenever am driving. Please I will appreciate your advice & suggestions.
Check for proper fuel pressure - both while the vehicle is running, and after running. I suspect you will find that fuel pressure is not being maintained in the pressurized portion of the system due to a fuel pressure regulator - which can also leak fuel (o-ring leaking). The inability to maintain proper fuel pressure overnight means the fuel pump has to work longer, while trying to start your engine, to get up to anything close to operating pressure so the engine will fire. Check the fuel filter for clogs as well. A clogged filter will hamper both startup and fuel pressure while driving. A YourMechanic certified technician can perform a Car is hard to start Inspection, or a Car is getting worse gas mileage Inspection, on your vehicle to help diagnose and repair this issue.