Fire crews from Albrighton and Telford were called to a fire on the eastbound carriageway between junction 3 and junction 2 at around 9pm on Friday.
One saloon car was found to be well alight and fire fighters took 30 minutes to extinguish the flames.
Just an hour after leaving the scene firefighters were called once again after a second car caught fire on the westbound carriageway between junction 2 and 3.
A fire appliance from Albrighton and two from Staffordshire attended and found the car to be completely alight.
The fire was reported at around 10.30pm and fire fighters, using breathing apparatus and hose reel jets took 40 minutes to out out the fire.