The recent emerging research Mobile Ad-hoc Networks (MANET) is a infrastructure-less network. All the nodes act as transmitter and receiver within their communication range and also act as medium. The main issues in MANET are to secure routing due to misbehaving attack preventing and having security from malicious nodes. In this recent research with the aim to filter misbehaviour attack, the author has proposed Intrusion Detection System (IDS), Enhanced Adaptive 3 Acknowledgement (EA3ACK) using EAACK (DSA) with (MARS4) hybrid cryptography for MANET. MARS4 which is a combination of RSA and MAJE4 is employed to reduce the routing congestion. Developed system that compares with five different scenarios through Network simulator (NS2) is used to implement and test the proposed system, providing secured transmission, and improving Packet Delivery Ratio (PDR) and throughput.