I am a co-signer on a vehicle, not the driver nor a penger, how much can I be sued for if no insurance?

The person on the registration can be sued in an accident. If you are only on the loan, you can only be sued if the car is wrecked and someone stops paying for it. One more thing, most loan companys can reposess a car if it is not insured even if you are up to date on the payments. Look at your contract.