I'm an idiot, mumbled the words I'm a mechanic when talking to French tourists.
Next minute I'm under their 1970`s Toyota camper which sports a shitty Aussie made engine trying to follow the vacuum lines.
Turned out the dude had fit new vacuum lines but messed up the breather and vacuum line so if he put his foot on the brake the engine would almost stall, haha!
Did they slip you s jambon in return?