popping only when accelerating?

It sounds like the engine is misfiring. Can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. You can upload it here with your response.

This guide may help us fix the problem:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

The cylinder compression should be about 140 PSI. This guide can help you run the test:

https://www.2carpros.com/articles/how-to-test-engine-compression

Please go over these guides and get back to us.

here is the popping noise the 2013 Ford Focus is making.

Thanks for the video. That is a good one, can you please remove the serpentine belt and then rev the engine again to see if the noise is gone, it sounds like the belt tensioner is having a problem. Check out the images (below). Please let us know what you find.

We disconnected the belt the vehicle is still making a popping noise in the intake and have they ever had problems with the phasers going out of time where this problem can happen the car has 173,000 if the ECU computer has a contest power .We own a mechanic shop in Peoria, Az my husband been a mechanic for 35 years he has never run into this problem with a 2013 Ford Focus 2.5L we had the vehicle here now over 3 weeks he has replaced coils, sparks plug, high pressure fuel pump mass air flow sensor we just not sure what is going on. Hopefully you might have an answer for us or if you could please give my husband a call regarding this car.

It sounds like you have a broken valve spring, can you remove the valve cover for inspection? Also, can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. You can upload it here with your response. We like to keep our conversation on the web so it can help others. You can have good compression and a broken valve spring. Check out the images (below). Please let us know how it goes.