Molecularly imprinted polymers (MIPs) have been combined with plasmonic probes to realize optical chemical sensors. In particular, plasmonic optical fiber probes are used as transducers to monitor several kinds of MIPs, such as nanoMIPs, MIP layers, and microbeads of MIPs. Plastic Optical Fibers (POFs) can be used to develop several bio/chemical sensor configurations, exploiting their excellent flexibility, easy manipulation, great numerical aperture, large diameter, and large number of modes. Therefore, extrinsic and intrinsic optical fiber sensing schemes can be achieved using POFs' characteristics combined with cheap equipment, such as white light sources and spectrometers. In this work, we propose a low-cost sensing strategy to monitor MIPs without relying on plasmonic phenomena. Intensity-based sensor configurations can be implemented by exploiting MIPs as the core of sensitive optical waveguides. In this case, when the binding between the substance of interest and specific sites of MIPs occurs, the refractive index of the core in the sensitive waveguide changes, and the intensity of the transmitted light also changes. This sensing strategy can be implemented using an LED as the source, photodetectors as the receiver, and an Arduino system to record and process experimental data. Several configurations will be presented in this work to demonstrate the capability of this sensing approach. In particular, as a proof-of-concept, furfural (2-FAL) detection in water solutions in food applications is presented, demonstrating high performance by achieving an ultra-low detection limit at the pico- to nanomolar level and a wide detection range spanning approximately four orders of magnitude.