During the final battles, there is a short chase-sequence where Justin Mckay (Mark Hamill) and Lawson (Michael Dudikoff) fall down a flight of stairs after bumping into a nurse. Before and after this scene, both their shirts are covered in blood, but during the scene they are white and clean.
In 2 instances, car collisions result in the cars bursting into flames. Petrol is not volatile enough to simply burst into flames.