FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P1128

DTC P1128: MAP Sensor Signal Lower Than Expected

1. Turn the ignition switch ON (II).
2. Check the MAP with the HDS or a scan tool.

Is 54.1 kPa (406 mmHg, 16.0 in.Hg), 1.6 V, or higher indicated?

YES - Intermittent failure, system is OK at this time.

NO - Replace the MAP sensor.