If you fail to pay EMIs for 2-3 consecutive months, then lenders will consider you as a loan defaulter. In such a case, late fee charges shall be levied on you, upon the unpaid loan amount. If you keep defaulting your EMIs, lender would send you notice requesting you to clear the remaining balance.
If, however you continue defaulting your EMI then lender would be compelled to seize your vehicle against which the loan was availed. Also your credit score will reduce and your credit report will have negative issues recorded.