Hi,
General help needed, I recently had a new plastic underguard fitted under my car (the plastic shield that goes under car/engine) as it come off in an accident.

I have recently noticed that when sitting in the car, the car sounds a little noisier, like a vibration, bit like an early blow in an exhaust sound.

When getting out the car, and listening, it just a standard diesel noise, so its only in the car can hear it badly? The car drives fine with no lack of power.

I have checked the plastic shield as thought that maybe loose, but its not, its fully secure, but do wonder if that is vibrating slightly?

Does anyone have any idea? I was worried the exhaust may have blown at top end where it connects to cat, but there is no sign off this, or any noise outside the car?

Just want some reassurance that all is OK, as not got sefvice until March (thankfully) and dont want to go to a garage just for this unless anyone thinks its serious)

Thanks all
Steve