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i'll get str8 to the point! i got my car checked out because the check engine light came on. the machine in which they used reported i had a bad o2 censor(one below the coverter). so i bought one for around 90 and replaced it myself. i unplug the battery to reset the ecu. when i have everything done and i plug back the battery in. i still have a check engine light on. i thought by unplugging the battery it'll reset the ecu? or am i mistaken? i asked someone and he told me that some cars retain the information so i had to drive the car for a while and the ecu should reset itself? is this true? i've driven my car for 60 miles now and the CEL is still on... i'm beginning to think i have another problem with my car.

oh ya, i got a print out from the person who did the CEL check for me. the code that came up was "p0136".

some advice would be appreciated... some info about my car if it helps any.
its a 96 honda civic dx, 216k miles on it... not sure if that helps any. i am somewhat of a noob at cars but i am slowly learning. so try to bear with me.

thanks.