Got an underbody rattle on the Audi guys. I've spent quite a bit of time investigating and I've drawn a blank so far.
At some point after fitting the AP coilovers I noticed it, quite some months ago now. It's best described as a rattle, very similar to when you shake a rattle can as though something is lose under the car, but it sounds like plastic - not metal necessarily. It's a tinny clangy' sound.
My plastic under tray has taken a beating in the past but I've taken it off, removed the cracked bits and placed it back on. This seems to be in place so it shouldn't be this (?).
I've also had the car on a Kwik fit MOT ramp where you syncronised the vibration of a rough road and nothing looked, sounded or felt lose (I was underneath the car while it was MOT test shaken). None of the exhaust components appeared, felt or looked lose - neither were the plastic items visible. It's a mystery thus far.
To summarise what I know;
- It's a tinny rattle can sound
- It's only reproducible when the suspension is worked on uneven ground or when on the down slope of a speedbump i.e. when the rear suspension lands back onto a flat from a raised environment
- Sounds like it's the rear of the car, but I can't be totally sure
- It's something that's in place but loose within it's position i.e. I've had a few 'three figure' MPH blasts to 'clear it out' and nothings fallen off yet
- I've checked in and around the wheels, nothing seems to be catching or stuck. No debris that I can feel or reach
The car is a 2010 Audi A3 Black Edition.
I totally appreciate any pointers, it's driving me mad as it's noticeable even with the windows up & audio off
Thanks.