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P0491 Diagnostic Trouble Code Discussion for April 2009

Secondary AIR System Insufficient Flow Detected (Bank 1)


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Trouble Ticket Help Requests for DTC P0491
Help Request Posted
2001 BMW 525i 2.5L MIL Lamp on VIN: WBADS43451
P0491: Secondary Air Injection System Malfunction Bank1. Hi, fellow techs, I need some help on this 525i wagon.The vehicle came in with multiple codes.I have replaced B2 S1 O2 sensor and broken PCV hose from crankcase vent valve to oil dip stick tube to fix lean codes and O2 heater code.Now,I have a problem checking...
April 02, 2009
2001 BMW 525i 2.5L Hesitation, MIL Lamp on VIN: WBADT43441
P0491: Insufficient secondary air flow. Hello, Need help on 2001 BMW 525i, secondary air pump code, thanks in advance for replies,hopefully some bimmer guys can help resolve, what i have is a secondary air pump code,P1491, and smoke tested system and found a number leaks under intake and hose at com...
April 13, 2009
2001 BMW 525i 2.5L Hesitation, MIL Lamp on VIN: WBADT43441
P0491: Insufficient secondary air flow. Hello, Need help on 2001 BMW 525i, secondary air pump code, thanks in advance for replies,hopefully some bimmer guys can help resolve, what i have is a secondary air pump code,P1491, and smoke tested system and found a number leaks under intake and hose at com...
April 15, 2009
2005 Dodge Stratus SXT 2.4L MIL Lamp on VIN: 1B3EL46J55
P0491: AIR System Performance. I thought I had this one fixed... MOD has very little information on this code, and my scan tool will not allow me to activate the pump. Instead, I connected my scope to the system to monitor it in action. I connected one channel to the relay control at the E...
April 16, 2009
2001 BMW 525i 2.5L MIL Lamp on VIN: WBADS43451
P0491: Secondary Air Injection System Malfunction Bank1. Hi, fellow techs, I need some help on this 525i wagon.The vehicle came in with multiple codes.I have replaced B2 S1 O2 sensor and broken PCV hose from crankcase vent valve to oil dip stick tube to fix lean codes and O2 heater code.Now,I have a problem checking...
April 02, 2009
2001 BMW 525i 2.5L Hesitation, MIL Lamp on VIN: WBADT43441
P0491: Insufficient secondary air flow. Hello, Need help on 2001 BMW 525i, secondary air pump code, thanks in advance for replies,hopefully some bimmer guys can help resolve, what i have is a secondary air pump code,P1491, and smoke tested system and found a number leaks under intake and hose at com...
April 13, 2009
2001 BMW 525i 2.5L Hesitation, MIL Lamp on VIN: WBADT43441
P0491: Insufficient secondary air flow. Hello, Need help on 2001 BMW 525i, secondary air pump code, thanks in advance for replies,hopefully some bimmer guys can help resolve, what i have is a secondary air pump code,P1491, and smoke tested system and found a number leaks under intake and hose at com...
April 15, 2009
2005 Dodge Stratus SXT 2.4L MIL Lamp on VIN: 1B3EL46J55
P0491: AIR System Performance. I thought I had this one fixed... MOD has very little information on this code, and my scan tool will not allow me to activate the pump. Instead, I connected my scope to the system to monitor it in action. I connected one channel to the relay control at the E...
April 16, 2009