I'd highly recommend following the advice of the Neuro here, you should have a cervical MRI along with a MRA of the vertebral arteries to rule out any dissection. It is possible from the accident you experienced a vertebral artery dissection (tearing of the vertebral artery inner wall in the neck). These arteries wind through the vertebra in the neck and can easily become damaged in an accident like from whiplash.
IMPORTANT: Until you have the Neuro exam and imaging, I would NOT have any kind of neck manipulation as done by a chiropractor.
More information is needed such as where the numbness is, which eye is affected, what kind of vision loss, how long the episodes are, the nature of your accident - head injury, loss of consciousness, your neurological examination, medications and drug use, etc... Based on the brief post, there a large numnber of things that this could represent including migraine, post-concussive syndrome, seizures, or TIAs among a number of other possibilities. Episodes of vision loss, especially if it's just one eye (in many cases like a shade coming over the eye) with neurological deficits are suspicious for blockage of one of the arteries in your neck or its branches. In a young patient, it's less likely to be due to typical stroke risk factors such as longstanding hypertension or coronary heart disease and more likely to be due to a primary disorder of clotting, drugs, or heart problem which allows blood clots to pass back up through to the brain. Another consideration given your recent car accident is a tear in the artery of your neck which can lead to clotting and stroke like episodes or TIAs. A formal neurological examination as well as imaging of your brain and the arteries there and in your neck with MRI should be considered. Good luck.