Turns over but doesn't start.
 

I have a 2012 Mazda 3, 2.0L. It turns over but doesn't start. I will sometimes smell fuel outside of the car. I thought it might be the Crankshaft Position Sensor but if you look at the dash pics while trying to start, the RPM needle is moving. Any thoughts other than replacing spark plugs?
https://cimg1.ibsrv.net/gimg/www.maz...ff4d6e296a.jpg
https://cimg2.ibsrv.net/gimg/www.maz...5939cf253e.jpg

***Update - Starts now. Finally got it to give me a code. I cleaned the mass air flow censor. Started but, idled a little low. I changed the spark plugs just for good measure and it runs like a charm now. I got lucky.