Novel interactive applications require small end-to-end latency for providing end users with good Quality of Experience. To prevent the bufferbloat problem causing increased delay, various AQM solutions have recently emerged. One of the most widely adopted method is called CoDel that detects the increased delay by maintaining the per packet sojourn times and compering them to a desired target delay. Accordingly, congestion situation is indicated when the sojourn time exceeds the target delay. CoDel applies a drop-based feedback to notify the responsive sources about congestion only when the deviation from the target delay is permanent. Dropping packets is then compensated by packet re-transmissions in case of TCP which worsens utilization. In this paper, we propose an ECN-enhanced CoDel that distinguishes between low and high levels of congestion, and ECN-marks or drops the packets, respectively. The performance of the proposed method is analyzed in thorough NS-3 simulations with variable number of flows. The proposed ECN-marking reduces the number of packets re-transmissions and provides similarly good characteristics including convergence time and fairness to the original drop-based CoDel.