2010 Synergy LLT M6 P0036 and P0056

[petercop]

2010 Synergy Green LLT with M6

Keeps throwing CEL for P0036 and P0056.

Was getting the P0420 but adding the CRC cat cleaner additive which cleared code and I passed NJ state emissions.

Checked O2 heater fuse and it is good.

Is it possible that both No. 2 O2 sensors heater circuits have gone bad?

Car has 112K. GM reman installed at 106K. I purchased with blown motor.

Running stock manifolds and cats. Other than CEL, car runs perfectly and I daily drive it to work (35 miles each way on highway)

My son had installed BBK headers and high flow cats I went back to stock as I could not stand the drone. Was only getting P0420 at that time.

No codes for sensor 1 on either bank. Just P0036 and P0056. No P0420 at this time.

I clear the P0036 and P00567 codes. They immediately go to Pending on restart and then Current on second restart. They are in history also.

Any suggestions.

Does anyone know what O2 heater resistance should measure in ohms?

[spyderbuddy]

cats could be bad, After my engine blew i had to replace the cats because the Antifreese Gumed up the Substrate. I Added BBK headers and High Flow cats, The PO 420 is the 2nd cat, They can be Tuned out All the O2 Sensors do is make sure they light at a Given Time

[DRC69]

Originally Posted by spyderbuddy

cats could be bad, After my engine blew i had to replace the cats because the Antifreese Gumed up the Substrate. I Added BBK headers and High Flow cats, The PO 420 is the 2nd cat, They can be Tuned out All the O2 Sensors do is make sure they light at a Given Time

Hi,
How many miles on the LLT before she blew-up? Sorry to hear.
THX