Wireless sensor networks (WSNs), due to their small size, low cost, and untethered communication over a short-range, have great potential for applications and services. Due to hostile environments and an unattended nature, they are prone to many types of attacks by adversaries. False data injection attacks compromise data accuracy at the sink node and cause undesirable energy depletion at the sink and intermediate nodes. In order to detect and counter false data attacks, a number of en-route filtering schemes have been proposed. However, they lack a strong false report detection capacity or cannot support network dynamics well. Commutative cipher-based en-route filtering (CCEF) is based on fixed paths, and a fixed detection probability, and does not consider the residual energy of a node. In an enhanced detectioncapacity and energy-efficient en-route filtering (EDEF) scheme, we use a fuzzy logic system which considers the residual energy, false traffic ratio (FTR), and number of message authentication codes (MACs) in a report to evaluate the fitness of a node to be a verification node. This helps to balance network energy usage and reduce the number of hops a false report may travel. The simulation results demonstrate the validity of our scheme with increased energy-efficiency (4.55 to 13.92%) and detection power (99.95%)