Saab OBD2 codes
Codes where we have reviewed, vehicle-specific evidence for this make.
Saab's notes come from factory service information rather than bulletins: check crankcase ventilation first for air-metering and lean codes on the 2008 9-3, and rule out exhaust leaks before replacing the converter on the 2005 9-2X.
C0186 and C0287 listed with a service stability light
A GM bulletin lists C0186 and C0287 among several codes that come with a service stability light on a 2006 mid-size SUV family. Only the NHTSA summary was read, and it lists the codes without a fix. The stability system is safety-critical, so have it inspected by a qualified shop. We have not confirmed the bulletin is still current, so this is labelled vehicle data rather than confirmed by bulletin.
P0101 and P0171: check crankcase ventilation first
Saab's service information for the 2008 9-3 tells the technician to check the crankcase ventilation system for leaks first for P0101 and P0171, because unmetered air there can explain them. This is factory diagnostic guidance, not a bulletin.
P0420: rule out exhaust leaks before the converter
Saab's procedure for P0420 on the 2005 9-2X has the technician clear other codes, check the rear oxygen sensor wiring and look for exhaust leaks at three joints before condemning the front converter.
C0186: Sideways (lateral) acceleration sensor signal faulty or not believable
- 9-7X 2006 · Supported by vehicle data · 1 bulletin
C0287: Stability computer flags a fault in a motion-sensing signal circuit
- 9-7X 2006 · Supported by vehicle data · 1 bulletin
P0101: Airflow sensor reading doesn't match what the engine computer expects for the throttle opening
- 9-3 2008 · Supported by vehicle data
P0171: Engine computer has reached its limit adding fuel on bank 1: the mixture is lean
- 9-3 2008 · Supported by vehicle data
P0420: Catalytic converter efficiency below the computer's limit (Bank 1)
- 9-2X 2005 · Supported by vehicle data
Sources and review
- GM 3741A: service stability light on, C0186 C0196 C0283 C0287 C0290 C0292 C0455 C0550 (2006 TrailBlazer family)
- Saab 9-3 (2008) WIS DTC P0171 00 (ME9): Long term fuel trim max value, air/fuel too lean
- Saab 9-3 (2008) WIS DTC P0101 00 (ME9): Mass air flow sensor performance (deviation from calculated mass air)
- Saab 9-2X 2.5i (2005) WIS DTC P0420: Catalyst system efficiency below threshold (bank 1)
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
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