Mysterious Knocking/tapping

[BBudensiek]

Hi everyone! New member here and first time poster!
I have a 2012 Limited with the 3.5 N/A with 137,000 miles on it. Within the last week It has developed this knocking/tapping sort of sound that comes in and out every 2-3 seconds. It seems to be louder after the vehicle is warmed up.
2 weeks ago, I did a coolant flush & a transmission drain & fill and oil change.

I do not hear the noise on the top end of the motor, you can only hear it when standing in front of the vehicle or can be heard louder while laying underneath. I hear it the loudest faround the front exhaust manifold/catalytic converter. I have used a stethoscope all over the motor/transmission and cannot hear it anywhere internally...
I am baffled by this... I am bringing it to my local ford dealer on friday but just wanted to get everyone's opinion on here as well!!

I tried to get a video of the sound but I do not know how to upload it on here. How do i upload a video?

 

[BBudensiek]

Here is my video

 

[mguy13sport]

Upload it to youtube. Does the sound match the RPM? You give it gas in park does the sound change?

 

[BBudensiek]

Upload it to youtube. Does the sound match the RPM? You give it gas in park does the sound change?

The sound is only at idle. I do not hear it at higher rpm, the sound does not change with any throttle at all, which is why I’m baffled by it lol

 

[peterk9]

The sound is only at idle. I do not hear it at higher rpm, the sound does not change with any throttle at all, which is why I’m baffled by it lol

Welcome to the Forum.
I am not able to see your video if it is posted. Could be my computer.

Peter