Some of the symptoms of PTSD most commonly experienced by those involved in serious car accidents include: Psychologically re-experiencing the trauma through intrusive thoughts or dreams about the accident. Persistent avoidance of thoughts or situations related to the accident. For example, a common symptom of someone suffering PTSD after a car accident is fear of or refusal to drive a car. Numbed emotional response, such as failing to produce emotional responses to the needs of others or feeling detached. Increased physical arousal, such as startling easily, becoming quickly agitated, or having trouble sleeping.