How old are the upstream O2 sensors? OL-Fault is open-loop fault, indicating problems with the upstream O2s. And your truck has misfires on both banks.

 

All of my O2 sensors were changed this Spring. I've had issues with the passenger upstream but it reads fine when my shop connects to it. I'm thinking that it needs to be replaced and I have a brand new O2 sensor. I'd do it myself but I cant seem to get my hand back there to unplug the connector which is frustrating. Removing it from the exhaust is easy. Any thoughts on how to get at that connector? Thanks so much for your help!

 

What brand O2 sensors are you using? Others here (and I) have had Bosch O2s that were bad out of the box. Happily it's been quite a while since I had to replace an O2, but if/when the time comes I'll go with Walker, which others here have reported better results using.

As for those connectors, try slipping it off the little mounting bracket to bring out from behind the head, then disconnect it. It's been years and years since I did this, but I recall you just have to lift up on it to slip it off the little bracket (but I may be wrong about that.)

Then, don't put it back on the bracket. I just let the one on my truck hang there so it's easier to access. If you later do that with the driver side O2 be sure to zip tie it in a place where the wires can't end up touching the exhaust manifold. (Ask me how I know ...)

Also, if you think the O2 connectors are a problem, the CKPS connector is even tougher to reach.

 

All 4 are Walker O2 sensors and I have a new Walker upstream as we thought that one was bad out of the box. Thanks for the insights in how to unclip the harness. I'll work on it this morning and let you know how I make out. Thanks again for your help!

 

I was able to reach the connector and replace the passenger side upstream O2 sensor with a new Walker unit. Test drive went fine but time will tell whether this makes a difference or not.

 

Fingers crossed.

FWIW, here are pics of the O2 sensor connectors on my truck.

As you can see, the one on the passenger side simply hangs free and stays plenty far away from anything it shouldn't be touching.

The other pic shows the Bank 1 sensor, which as I said is zip tied keep it away from the exhaust manifold. Before I did the zip tie, I got lucky and found that insulation on one of the wires had started melted slightly. What I didn't recall is that I crafted a loop out of some plastic plumbing strapping and attached it via the nut you can see to give something for the zip tie to attach to.

 

Well, so much for that. Now I'm getting a P0150 code on the brand new O2 sensor. I was sure to "click" the plug into the harness but I'll have to get back in there tomorrow and make sure that it is fully connected. I sprayed CRC electrical cleaner into the harness connector which was actually really clean. I suspect that my shop cleaned the connector when they installed the new O2 sensors this Spring. Getting P0300 and P1300 codes as well.

 

Double bummer.

I just noticed your location is listed as Upstate South Carolina. Greenville-Spartanburg? I'm in Charlotte.

 

Doesn't Open Loop refer to the ECU mode, that is not Closed Loop control. The mode is Open Loop if the ECU is not using feedback from the O2 sensors.

 

Correct