So, I've been working on my "750$ special" 02 disco. I bought it because the front drive shaft had broken and hit one of the catalytic converters....causing it to partially run rough. Pulled the o2 sensor out in front of the damaged cat and started it right up! Ran perfect and drove it a couple blocks to my driveway.

Ordered a new Y-pipe, 4 new direct for Bosch o2 sensors, CPS[CKP], and exhaust gaskets. Got it finished up today. Started right up and ran well. Got a code p0134[bank 1, sensor 1] and P0453[tank pressure]. The previous owners had a shop in Florida "fix" it and they poorly spliced in a ****ty GM harness in between the o2 connector/harness because the wires melted at the clip at some point. I went to the local junk yard and got the right clip/pigtail. I butt spliced the new wires, as the area on the driver side is a pain and didn't want to remove the whole harness/intake. I wish I could have soldered it. So I figured there is an issue there and will check it tomorrow. I noticed on my scan tool, with the ignition on, the live data shows the o2's are getting .450 volts, except one, which shows 0.00 volts. Is there a way to check the the voltage on the engine harness/connector? Just in case my connections are ok and the o2 checks out?

Also, I needed to bleed the coolant, so I turned it off and let it sit as I went to go get my big flat head screwdriver. Came back 30 min later and it just turns over but doesn't start. Thinking it was the inertia switch, I try to reset it, but no luck. Tested the switch and it is ok. It got dark and I called it a day. Today, I checked the CPS[CKP] and connection. I Checked for spark and everything seems in order. My guess is the fuel pump and/or relay took a dump....it does have 144xxx miles, so I can see it happening. Any way on checking it? I do not hear the pump run when I prime it at start up.

As for the evap/gas tank pressure code, I put a new gas cap on that I had laying around and the code returned.

Thanks again!

 

So I ordered a new fuel pump and sealing ring as I couldn't hear the fuel pump working. It needs to be changed anyways, as it is about time.

Installed a new purge valve, as they do fail and are pretty cheap.

Also, I got a new scanner today and fully updated it. The Autel AL619 is pretty good for the price. A little pain in the *** in order to update if you only have MAC and no PC.

After using this new tool, It is showing the o2 sensor, Bank 1 sensor 2, is not working correctly, voltage reading .000.

I get underneath and disconnect it, inspecting the pins, and connect it back together. Scan tool now reads .010 voltage. All other sensors read .450v.


So, tomorrow I am going to swap the sensors and see if there is an issue with the sensor. Both rear sensors are warm to touch, so the heater circuit is working correctly. Is there a way to test the voltage on the wiring harness at that o2 sensor?