I did an OBD1 conversion on my 91 Civic, and wire 8 on the conversion harness is supposed to be wired for the check engine plug.

I was told the blue plug below is the check engine plug for the EF to check for CEL codes.



wire 8 is one-wire, while the plug is 2. do I just connect both wires into one? that doesn't sound right at all.

 

I didn't think there was a factory plug to check CEL's on 88-91.....

I have no idea what that blue plug is though.....

You should probably just hook 'wire 8' up to a switch, that when flipped, will ground it out. Then the codes will blink on your cluster like regular obd1 cars.

 

yes 88-00 civic has them the blue wire is to check cels by jumping the plug. get a papeer clip or wire and stick it either end of the plug. i have a obd1 converted 91 hatch and i just checked for cels this past weekend by way of the blue plug and the check engine light in the instrument panel.

the blue plug should be there from factory and should not need anything added to if i remember correctly.

 

no it isn't. it's the grn and brown wire (blue plug). hit the two blues and your going to blow a fuse. my harness is differnt for my obd1 setup. I have a small sub harness which has wires for the o2, knock, vtec, and check engine.



Modified by dem0nk1d at 1:34 PM 8/22/2007

 

my wording was a little off but it is the blue plug with the green wire with a white stripe and the brown wire. these two wires goes into the blue plug. this is what you check cels
from.

 

if the jumper harness comes with a wire for checking CELS, does that mean I can't use the blue plug? or would the blue plug still be hooked upto the ECU?

 

if the jumper harness has the CEL wires, why not just use those?

 

Use the wires supplied with the conversion harness. I have the same conversion harness and I run the 2 wires (from the con harness) to a switch located on my dash. Whenever I need to check for cel's simply "flick the switch".