So I got this new to me 2015 Ecoboost. After a few days, I started to closely look at things. First thing I noticed was my Volt reading on the driver cluster reading at 13.7, I'm used to seeing 14.1-14.3 on most vehicles. So I hook up my OBD2 Bluetooth adapter so I can see what the car is doing, using my Torque app, it's reading 14.2 which is normal to me. I cleaned the terminals and re tightened the connections, took to the parts store and had them test the battery and alternator, both passed with no problems.

My questions are, can the sending unit have gone bad? Is there a sending unit for the alternator? or Should I not even worry about this....which is what I'm forced to do anyhow?

What my Torque app shows

 

I took a two week trip in my 2016 GT the beginning of August. I noticed that sometimes, the voltage would read ~14 and other times, it was as low as between 12.5 and 13 volts. I used to drive an '08 F350 Superduty for work and it would do the same thing. I think what's happening is, after a start, the charging system is recharging the battery. Once the battery is back to full charge, the charging system cuts back to a maintenance mode. It's supporting the cars electronics but not much else. When I was on that trip and saw it down toward 13 volts, I started checking on it every 15 to 20 minutes. I found that it would stay down around 13 for a while, then pop back up to 14 to 14.5 and it would cycle like that all day. When I stopped for fuel or food, I'd check it after restarting the car and it would be back in the 14 volt range again for a while recharging the battery after the restart. So for now, I'd recommend you just keep an eye on it. If it goes back up the 14 volt range after starting the engine, then I wouldn't worry about it. Good luck.

 

The A/F ratio being at 14.1 means 14:1. The Torque app shows decimals
beyond what the cluster is capable of. So, you see 14.74:1 because
the dash only has xx.x positions there. If it were to drop to 13.xx:1, your
dash would just show 13.1

Temp was rounded up, doesn't provide a decimal position for that data.

The voltage discrepancy at the dash is common...

 

I have found out why the alt does this, it's like you said, after charging the battery it goes into a maintenance mode.

Thanks for the info, even after having the Torque app since 2011, I'm still learning things about it. I have figured that, if the numbers are close to normal with no crazy spiking, I'm good.