Emerging technology allows the users to access information and services anywhere regardless of their geographic location. Mobile Ad hoc Network is the significant technology among various wireless communication technologies where all the nodes are mobile and which can be connected to dynamically used wireless link in a random manner. The selfconfiguring ability of nodes in MANETs made it popular among critical applications like military use or natural emergency recovery. Most of the proposed protocols assume that all nodes in the network are cooperative, and do not address any security issue. To adjust to such trend, it is vital to address its potential security issues. The main objective of this paper is to define the path for security and to further improve throughput, routing overhead, packet delivery ratio and at the same time to create energy enhanced way with excellent security. Implementation of cryptographic algorithm for the information is done in such a way that it is impossible for the attackers to knock the resources of information sent on the web. In this paper, a new intrusion detection system, Energy Efficient Enhanced Adaptive 3 Acknowledgement (EE-EA3ACK), using EA3ACK with Elliptical curve cryptography is (ECC) specially designed for MANET. In this ECC there is a two key encryption technique based on elliptic curve based theory that can be used to create faster, smaller, and more energetic and efficient cryptography. Network Simulator (NS2) is used to implement and test the proposed system. The proposed cryptography provides secured transmission, further it reduces routing overhead, improves packet delivery ratio and throughput.