Honda 2011

Hi Guys/Gals
I have a question/concern about the noise coming underneath the car for last 2 days since my oil change. It usually comes when I hit the break and sometimes when I press the accelerator. It does not happen all the time and it shifts the place. Something it is in the middle section of the car and sometimes it comes from the back trunk area.
The sound is similar to the one if some heavy piece of luggage would hit the trunk wall if you were hit the break. I usually keep my dad’s wheelchair in the trunk so initially I thought that is the case. But then I removed it that noise still comes.
Sometime I can relate to that banging noise as if a pipe is contracting or popping due to the change in temperature or may be pressure. But this is just my assumption.
Any idea what is going on?

When the oil was changed, did they also rotate the tires?

I would suggest that you check that the spare tire is firmly bolted in place in the trunk, as a loose & shifting spare tire could certainly explain a noise that is heard when you hit the brake and/or the accelerator.

Yes, also check the jack. If it’s not clamped firmly in place it can slide around and make a clunking sound.

Could be a broken tail pipe hangar.

My mom had that kind of noise and when I checked it out it was a srpay can of window cleaner rolling and hitting the passenger seat frame.

But I would check the lug nuts too. Maybe they forgot to tighten one wheel down.