Oxygen Sensor?

[Shoboy3]

Well on a 30 mile trip today I decided to see what the car would do. At about 105mph in 4th the check engine light came on and stayed on for a minute or so then went off. Next it proceded to come on later while going about 70mph in 4th up a hill.

Got home and pulled the codes:

111 Systems Pass.

111 Systems Pass.

1

176 HEGO sensor indicates system lean (LH).

176 HEGO sensor indicates system lean (LH).

So, can anyone explain to me what this means? I am not sure if it means the O2 is stuck making the car run lean or if someone else is making the car run lean and the O2 indicated this.

Thank you.

 

[twr]

Typically when only one O2 sensor throws a code, it's the sensor that has gone bad. You should replace both of them.
Terry

 

[Sam]

Check for voltage from the O2 sensor(s) when running and hot. If you have variable voltage, then the O2 sensor is probably ok and you have something causing the lean signal (e.g., air leak). No voltage = bad O2 sensor. wink

 

[sdpatt]

twrsho gave good info. Since only one sensor read lean, the problem is most likely with the sensor. If both sensors read lean (or rich), the problem is most likely with the engine control system. I recommend the Bosch sensors and they can be found at AutoZone as shown.

3.0L: Bosch 13942, AutoZone/AutoZone.com $33.99+tax

3.2L: Bosch 13223 or 15716, AutoZone/AutoZone.com $40.99+tax