The research evaluated the spatiotemporal variability and acoustic criticality of environmental noise in the Terminal Terrestre corridor, El Palmar–Tohallí, Manta canton, Manabí province, Ecuador. Six points associated with transport, commerce, public facilities and spaces of urban permanence were selected. The design included 90 LAeq monitoring units, 15min (6 points × 3 operating periods × 5 days); Supplementary Material S1 retains 450 associated analytical records, identified by provenance and not treated as additional independent observations. The instrumental control included 30 pre- and post-measurement tests at 94.0 dB and 1 kHz, with a maximum drift of 0.1 dB and an expanded operational uncertainty of the instrumental component of ±0.7 dB (k = 2). The reference weather conditions were compatible with the protocol, with no rain during the measurement windows and with wind less than 5 m/s. The levels were contrasted with Ecuadorian environmental regulations and were complemented with temporal amplitude, time shift of critical areas, spatial gradient and IDW interpolation. Spatial cross-validation produced RMSE of 3.05, 3.33 and 4.00 dB(A) for morning, noon and afternoon, respectively, so the maps were interpreted with exploratory scope. The Urban Acoustic Criticality Index (ICAU) integrated regulatory exceedance, sound intensity, temporal amplitude, spatial gradient and functional sensitivity. The six points did not comply with the applicable limits, with averages between 82.1 and 87.3 dB(A). The sensitivity analysis using 19 scenarios maintained the order P5–P1–P2. An AHP technical-documentary scenario, with CR = 0.0189, maintained the same priority group and showed a Spearman correlation of 0.943 with respect to the operational scheme. In addition, internal temporal validation by successive exclusion of each day retained those top three positions in five of five iterations and produced Spearman correlations between 0.943 and 1.000. It is concluded that the corridor has high and spatially differentiated acoustic pressure; the AHP justification, the sensitivity analysis and the temporal verification support the coherence and stability of the ICAU as a technical-operational tool within the corridor studied.