bad gas mileage
almost any malfunction in your car can cause a drop in gas mileage (including the cam sensor) any time when your engine has to try harder to do what it is meant to do or is confused, and has to guess, due to a bad sensor it can cause poor mileage, and even further damage to your vehicle ex: a bad cam sensor can also make starting your car take longer possibly damaging your starter.
A bad O2 sensor can affect gas mileage. It is an emissions sensor, so when it goes bad, it does not reflect emissions performance on the car, which could cost a lot in gasoline.
Yes
poor gas mileage
Improper fuel mixture, can make the car harder to start and run rich. Worse gas mileage
Yes it certainly could cause bad gas mileage especially if it is plugged up or if your car's oxygen sensors readings are faulty.
if your check engine light is on change your o2 sensor. a bad o2 sensor will cause bad gas milage. also a dirty air filter or dirty injectors.
causes very poor gas mileage
Generally a Bad Oxygen Sensor will cause the engine to run too Rich...too much gas mixed with not enough air. This will decrease Gas Mileage, and lower the engine's performance. Also the Check Engine light will come on!
No, a bad fuel pump will cause a no run situation.
It could, yes.