An enhanced "Trust based Genetic Neuro-Fuzzy system for Intrusion Detection and Self Adaptive Firefly Integrated Particle Swarm Optimization"(GNF-SA-FPSOIDS) based Routing Algorithm is proposed. In the initial stage, four trust factors, such as direct trust, indirect trust, recent trust, and historical trust are calculated and provided to the genetic neuro-fuzzy system. It generates the fuzzy score for each node and declares the node as 'trust node' or 'malicious node' based on a predefined threshold value. After obtaining the trustworthy nodes through genetic neuro-fuzzy system, the possible paths in MANET with trust nodes that are suitable for data transmission are identified. Here, the SA-FPSO algorithm is proposed to identify the optimal paths among the possible paths and data transmission is done through the optimal paths.