o2 sensor unplugged

[2blue4you]

I have a 95 chevy k2500 454. Just had a new exhaust put in(everything new from y pipe back), and they mentioned that my o2 sensor at the y pipe is unplugged. I can see the plug dangling but can't find the male end of the connector. I've been searching the forums and it seems like I am looking for a dark purple wire. The only dark purple wire I can see comes down near the o2 sensor but looks likes it goes to the starter. The transmission, transfer case, front differential, and engine have all been out of this truck recently, so I'm at a loss. Any ideas where I could find this connector, and if it's been cut or lost, how to get this o2 sensor hooked up.

 

[Schurkey]

Download the service manual set for your vehicle from the links in the "Sticky" section.

You'll find the wiring diagram, for confirmation of wire color.

After that, it's just a matter of hunting around for the connector--or, worst-case, finding the remains of the wire where it's been ripped or cut off. Which might mean tracing the wire from a connector farther-up in the engine compartment. Again, the service manual will tell you where the connector(s) are.

 

[RichLo]

Do you have 3 others plugged in (2 pre-cat and 1 post cat after the Y-pipe)? It could be the 4th plug used for post-cat on a dual exhaust.

 

[2blue4you]

I looked at my Chilton

Download the service manual set for your vehicle from the links in the "Sticky" section.

You'll find the wiring diagram, for confirmation of wire color.

After that, it's just a matter of hunting around for the connector--or, worst-case, finding the remains of the wire where it's been ripped or cut off. Which might mean tracing the wire from a connector farther-up in the engine compartment. Again, the service manual will tell you where the connector(s) are.

That's what I did. Took me a solid 2 hours to find the connector. It is small purple wire, of which there are two solid purple coming off of ECM. They both went behind the distributor and then down beside the block on the driver side. Poked around a bit end eventually found the connector high up almost on top of the transmission on the driver side. Also found another connector hanging loose with this one, no idea what that is. The wire wasn't long enough to plug it in but tomorrow I will replace the sensor and hopefully I can get a new one with a longer lead.

Thank you for the help

 

[Schurkey]

I looked at my Chilton

Do yourself a favor. Put the Chilton manual in the trunk or under the seat, so when you're on a road trip and need emergency toilet paper, it's there and handy.

The Genuine GM service manuals have Chilton/Motor/Clymer manuals beat in all sorts of ways.

 

[GoToGuy]

It's a 95 so it's not OBD 2, should only be one O2 sensor pre cat.