Most days the car runs okay. Periodically when it's very cold (below 25 degrees) the car won't start. New battery, everything works well as to lights, radio, etc. No starter problems that I've noticed. It's so strange. I turn the key, listen for the fuel pump, and begin to start the car. The motor turns, but it won't start. I do smell a little fuel from time to time, that's constant but it dissipates after the car starts (if it starts).

Is it flooding somehow? Can an O2 sensor stop a car from starting? Is that the problem? I don't step on the gas pedal. This always happens in cold weather. I can let the car sit for a day or so after not starting, and if the temp outside is a little higher, it will chug to a full start. Aggravating!!! Is Car MD any good? Help, and thanks.