What has been noticed since yesterday, always while driving (without effort of the engine) i.e. 50 km/h on a straight block, if you hold the gas, the 50 stay, you hear a horn from behind!!! If you give more gas it is gone, is also gone if you take gas away!!! No matter what speed you drive, if the engine doesn't have to exert itself, you can hear this annoying horn!!!

What can that be??? Comes directly from behind!!! Axis???
HELP!!!
Thanks to you
Ciao
Jens

Marius
Marius