Codes P0455, P0136, & P0174. Where to start?

[Shukonda]

I just went to Autozone and got the Explorer's check engine light ran for codes and these 3 came up. Are they related? I got a bottle of fuel injector cleaner and so far put 45 miles on so I don't know if I have to wait longer to see any results, but that's what Autozone told me to do first. Can anyone steer me in some type of direction because I am lost on where to start. Any info would be appreciated. Thanks.

Oh it's a 99 Explorer 4x4 OHV. Thanks.

 

[tmds3]

Well the P0455 code is for a possible bad gas cap so fuel system cleaner wouldn't help that.
The other p0174 could be a MAF or just a vacuum leak behind the MAF sensor
P0136 could be a bad o2 sensor.

Good Luck