The car owner contacted the AA after the cub was seen darting under a wheel arch and up into the engine bay of the Audi SQ5.
Patrolman Jason Robertson spotted a dangling leg and was able to pull the animal - which had made its way into the gearbox - free.
The cub, now named Basset, was unhurt.
He is being looked after by staff at the Scottish SPCA's wildlife rescue centre in Fishcross.
Mr Robertson, who has worked for the AA since 2006, said: "When I saw the job come up with 'fox in engine bay' I feared the worst. I thought maybe it had been hit and I would be arriving at quite a gruesome scene, but I was pleasantly surprised to find that wasn't the case.
"The SSPCA were there but had been unable to find the fox. We tried to coax it out with cat food but when that didn't work, I jacked the car up and saw one of the cub's legs dangling down. Luckily, it was pulled out unscathed.
"I've rescued plenty of kids from locked cars, but this was definitely a first for me."
Scottish SPCA centre manager Colin Seddon said: "Basset appeared unharmed and is doing well now. We'll keep him in our care until the summer when he'll be released back into the wild with a number of other fox cubs at a carefully selected site."
A fox cub is recovering at an animal centre after being rescued from the gear box of a car in Aberdeen by an AA patrolman.