Q: Check engine light when running heater.

asked by on January 04, 2017

I usually head to work early and sit in my car for a bit before going in. With the colder weather here, I sometimes let the heater run. After only a couple minutes, the check engine light comes on (codes P1166 and P1167) this only happens when I'm sitting idle while running the heater. I can go weeks of driving and running it wroth no error, until I sit for 5 minutes without driving.
Any ideas?

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Hello, thank you for writing in. Lets discuss the codes individually. The P1166 stands for the air/fuel ratio sensor giving you false readings. This may be due to a poor wiring connection, or a failing sensor. P1167 is telling you that the issue is electrical and most likely not a symptom of the vehicle’s engine malfunctioning. At this point, you will want to double check the connection to the sensor and make sure it is clean, dry, and tight. If the connections look fine, chances are there is an issue with the sensor itself, and it will need to be replaced. For more help resolving the issue, contact our service department to schedule an appointment.

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