2014 5.7 Losing power Intermittently

One month ago I started losing power while driving at a variety of speeds and temperatures. It would simply die down and idle while the accelerator was still depressed. If you release the accelerator then reapply it would pick up again then cut out shortly after. I took it in to pull codes and left it with the dealer for the week. They ran it for 300 miles without reproducing the same failure. Without incident I made a 2,000 mile road trip with a trailer. One month later it stated the same failure. I changed the Mass Airflow Sensor. Now the RPM's take a dive when it starts (almost cuts out) and I have check engine indicator. Is there something about the sensor I need to adjust or do I need to start looking somewhere else?

 

Welcome from the Texas Hill Country.

Intermittent, non-repeatable issue sounds like accelerator pedal or throttle position sensor/throttle control motor problems to me. Accelerator pedal is fly-by-wire. Diagnosis of throttle body problems can be done with Techstream, but your dealer has to hook it up for it to work.

 

How many miles on your truck?

 

I had a similar issue with an older Honda Accord; turned out to be the ignition coil. Not sure if that’s possible in these trucks but had the exact same symptoms

 

How old is battery?