U0157 Pontiac Montana is defined as Camshaft Position Sensor A Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading. As you drive and when specific conditions are slowly met, the vapors will gradually purge from the charcoal canister and will get burned within your engine.
SymptomsSymptoms of a U0157 Pontiac Montana diagnostic trouble code may include:
Possible Causes :
With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications.
Diagnostic trouble code U0157 Pontiac Montana is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.
Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before U0157 Pontiac Montana.
Fortunately, U0157 Pontiac Montana is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.