How to Troubleshoot Code P0420 on a 1999 Pontiac Montana?

Answer Receiving a diagnostic trouble code of "P0420: Catalyst efficiency below threshold" from a scanner hints at why the check engine light on your 1999 Pontiac Montana is on, but it provides no informa... Read More »

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The Location of the Speedometer Sensor on a 1999 Pontiac Montana?

Knowing how to locate various components of your vehicle is important in proper care. The vehicle speed sensor is a small electrical device that reads the rotation speed of the transmission shafts.... Read More »

1999 Pontiac Montana AC Pressure Sensor Location?

The AC pressure sensor in a 1999 Pontiac Montana minivan is designed to relay information about the refrigerant pressure to the powertrain control module (PCM). The PCM uses this information to mak... Read More »

1999 Pontiac Montana: I Replaced the Intake Manifold & My Van Still Won't Start?

Troubleshooting a vehicle that won't start can be a hassle. There are always several diagnoses with a no-start engine. While replacing the intake manifold on your 1999 Pontiac Montana may have been... Read More »

Symptoms of a 1999 Pontiac Montana Blown Head Gasket?

If you drive a 1999 Pontiac Montana and suspect your vehicle's head gasket is blown, there are several signs that can confirm your suspicion. If your vehicle is displaying any of these symptoms, it... Read More »