Honda D Series Forum banner

1 - 9 of 9 Posts

·
Registered
97 civic DX
Joined
·
232 Posts
Discussion Starter #1
I have a header that has only one O2 sensor onit. I just unpluged the other one am I hurting myself. So that means I have a check engine light . I heard that put the ECU in a limp mode . I have ran a 16.6 1/4 that seems to be pretty good for a non vtec N/A car.
 

·
Registered
Joined
·
1,170 Posts
Your check engine light is ON instantly because you unpluged your 2nd O2 sensor.......the ecu dont see any resistance between 2 wires of the 2nd sensor(dont remember which one now...)and you get a code for the 02 heating circuit.......
If you let your second O2 sensor pluged, the check engine light will only be ON after the SECOND or third time you drive the car and you will get a code for the O2 output circuit......
In my car, the second one is pluged but not installed in the exhaust....BUT I unplugged the wire that give power to the ecu when the ignition key are at the off position. So each time I shut off the engine, the ecu lose his memory! That way, the check engine light never come ON because of the 2nd o2 sensor!

From my experience, when the check engine light is ON because you disconnected your 2nd O2 sensor, you lose some power! The CEL come ON one day when I was at WOT (when I didn't remove the"memory" wire from the ecu) and I felt the difference when it come ON!!!

An O2 simulator can fix your problem too....
 

·
Registered
Joined
·
2,515 Posts
I left my second O2 hanging in the engine bay for months without throwing codes...
 
1 - 9 of 9 Posts
Top