Electrical New O2 sensor harness has no jumpers (91/93)…

[afjLX]

My lx 5.0 hatch had on off-road X with no o2 sensors or harness (previous owner did this) running a A9L ecm. . Main sensor connection still existed near the passenger fender. So I installed 2 new Bosch sensors and ordered a new sensor harness from LM r. This new harness does not have the jumper on the plug. It doesn’t even have a pin in one of the connector holes where this jumper would go. I verified all connections and voltages at the sensors and connected everything up. Car starts fine and all of the o2 codes disappeared. Do I need this jumper? Or just run it?

Update to this:
So I previously had code 67 (neutral safety switch error) and could not run the KEOR test to scan codes. Jumpered pin 30 to ground to clear this so I could pull codes. I left this connection tied to ground. After doing more digging, it appears the loop in the o2 harness is tied somewhere to pins 30 & 46. So my question is should I remove the ground connection on pin 30 and run the loop wire jumper at the o2 sensor harness? Is there any reason I can’t just leave pin 30 connected to ground and ignore the o2 loop?

Update 2: I went ahead and installed the jumper on the o2 harness and removed the chassis ground to pin 30 at the ecm. Code 67 never popped up as expected. So I’ll install a permanent jumper at the O2 harness and run it that way.

 

[gkomo]

Did you fix code 67 or just bypass? Sorry not exactly what you’re looking for per your thread.

 

[afjLX]

Did you fix code 67 or just bypass? Sorry not exactly what you’re looking for per your thread.

Well, I still have pin 30 connected straight to chassis ground which has eliminated code 67 for the neutral safety switch. I may just try to add the o2 jumper at the harness and remove the pin 30 ground connection I made and see if that does indeed eliminate code 67 as expected. I’m just wondering if it’s even necessary? Can I just leave pin 30 grounded? Does the O3 loop serve any other function? The LMR 91/93 O2 harness does not have a jumper wire on it.

 

[gkomo]

I’m not sure but my KOEO pulled a code 67 so I bought a new neutral sensing switch, the one that goes up on the front top of the transmission, in hopes of fixing that. Was curious if that’s what you did.

 

[afjLX]

So I went ahead and installed the jumper on the o2 harness and removed the chassis ground to pin 30 and that did as expected. No code 67 popped up.

My ‘87 is a 4cl to V8 swap and doesn’t have the clutch pedal switches mounted. Previous owner did the swap and didn’t bother mounting them. So I’m sure the switches at the transmission are jumpered out. I do plan on installing the pedal switches and trans switche and making everything right eventually.