Is it permissible to use surplus petroleum coupons granted by the company to pay for personal car violations?

It is not permissible to use the surplus from work vehicle fuel coupons for private purposes, such as paying fines. Rather, they must only be used for the benefit of the work vehicle, because you do not own the coupons unless the company has transferred their ownership to you. Similarly, using the work vehicle for personal purposes is not permissible except with the permission of the employer.