Single "Pop" noise from beneath 2003 C4S 33k miles.

[dad2n2]

Occasionally, when moving the car from parked position either forward or reverse i get a loud "pop" as if something was binding then released, best i can tell its coming from front right. I can't see anything obstructing any of the suspension or axles... anyone experienced this?

[Loren]

Check the upper strut mount in the front trunk. Not uncommon for the bolts to come loose and have the upper strut move under load.

[RFM]

I would also take a look at the brakes, maybe there remains a sticking pad.

[dad2n2]

ok, i will check both and let you guys know... thanks! hard to pinpoint where its coming from as its loud like a rock hitting the door panel...

[RFM]

Good that you mentioned, where it seems that the noise coming from around the door, try with the door open, sometimes it comes from the hinges or door catcher.

[roadsession]

after a car wash or wet run brakes will do that.

[valfam]

Front bearings? Brake caliper lose, Bushings. Try this. drive at a few miles per hour then stop hard. then back up see if it pops when you back up? if it does then have someone stand by the car do it again. I once worked on a car that would only do it in the morning. when backing up out of the drive way. one that one it as front week bearing they would stick being parked all night but during the day it was fine.

[dad2n2]

Front bearings? Brake caliper lose, Bushings. Try this. drive at a few miles per hour then stop hard. then back up see if it pops when you back up? if it does then have someone stand by the car do it again. I once worked on a car that would only do it in the morning. when backing up out of the drive way. one that one it as front week bearing they would stick being parked all night but during the day it was fine.

Ok, this makes sense as it only happens in the morning or when car has sat for a long time. I will take a look at this as well.... so hard as its very difficult to repeat on demand.