I did my Search. I found out what the code means.
P0137-O2 sensor circuit low voltage (bank 1 sensor 2)
My current set up and issues r listed:

-Injen cai
-Tsudo header
-Tsudo S pipe with a 90degree antifouler
-30inch. resonator
-Tsudo mid pipe
-HKS Exhaust

My CEL only comes on the freeway driving over 60mph. City drive I get no CEL. after reading about code P0137 i still don't get what it means.
Do I need to replace my O2 sensor or i need to replace my 90degree antifouler or I need to replace the 90degree fouler to a straight spark plug fouler?

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If i need to do the spark plug trick how many do i need. some other advised 1 some 2 or even with 3. I'm lost with this problem. any inputs r welcome............. Thanks...........

 

i forgot to mention the cel goes on when im using the heater for more than 5 mins..... other than that my car is good.....

 

my bad

 

Is that a BLATANT threadjack?


My guess is that there's a dirty connection somewhere, or like you said you need to do the spark plug anti fouler trick. Add one see if it stops, if not add another.