Insight Please

[josephcotoia]

Hello,

i have a 2007 Chevy Aveo LT and it has been throwing quite a few codes at me recently. Seven to be exact, particularly revolving around the Catalytic/O2 sensors. If anyone could help me with some guidance and what I should be doing then would be wonderful. I have considered replacing the catalytic and sensor but was wondering if this has affected others. I would prefer to start from step one whichever that may be instead of just replacing everything when it possibly could be the smallest thing. Thank you in advance!!

I have listed the codes Below....

P0128: coolant Temp Below Thermostat
P0133: Oxygen sensor
P0134: Oxygen sensor
P0420: Catalytic system efficiency below threshold
P0137: Oxygen sensor circuit low voltage B1S2
P0131: Oxygen sensor circuit low voltage B1S1
P2297: Oxygen Sensor Out of Range During Deceleration Bank 1 Sensor 1

[avguy]

Always best to diagnose instead of just throwing darts by hanging on parts. The first thing I would do is test the battery and load test the charging system with a multi-meter, and cross-check that by having them tested at one of the auto parts stores. Then, if everything in the charging system checks out ok, testing voltages in the O2 and coolant temp sensor circuits would be my next step.

[xintersecty]

I wonder if the ground for those circuits are shared. If you use a multi-meter you can check that. In other words, what he said!

[avguy]

I wonder if the ground for those circuits are shared....

That was my first thought as well, but then I remembered that the O2 sensors are grounded by the ECM. And, when I checked the coolant temp sensor, its the same for that one as well. So hopefully it will be something simple, such as a battery on the way out, instead of the higher priced ECM. But of course the ECM connector and wiring are in the mix as well