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P1131 Diagnostic Trouble Code Discussion for May 2011

Heated Oxygen Sensor (Bank 1 Sensor 1) Indicates A/F Ratio Too Lean


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Trouble Ticket Help Requests for DTC P1131
Help Request Posted
1998 Ford Escort SE 2.0L Excessive Emissions, MIL Lamp on VIN: 1FAFP15P4W
P1131: lack of o2 switching. Came in for 3% NOx on emmission. 1% is max. typically. Hooked up Modis and Launch. Front O2 reads 0 steady. LT and ST trim reads 0 steady. Rear O2 bouncing around. We've replaced both O2's and used PCM. Backprobed on computer connections, front 02 and rear O2 ...
May 18, 2011
1998 Ford Escort SE 2.0L Excessive Emissions, MIL Lamp on VIN: 1FAFP15P4W
P1131: lack of o2 switching. Came in for 3% NOx on emmission. 1% is max. typically. Hooked up Modis and Launch. Front O2 reads 0 steady. LT and ST trim reads 0 steady. Rear O2 bouncing around. We've replaced both O2's and used PCM. Backprobed on computer connections, front 02 and rear O2 ...
May 18, 2011