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dereku
11-12-2009, 09:18 PM
When I bought my 97 GT the owner told me the check engine light had been on for three years. I haven't checked the code yet, but I took a look under the car to find the downstream 02 sensor (after the cat) not plugged in. The 02 sensor has a trangle like plug. The factory harness, and the square plug from a previous 02 sensor, with the wires is just hanging there. It looks like they may have put the wrong 02 sensor in, and gave up when they couldn't just plug it in.

Both 02 sensors are three wires. Two white, one black. Can I just cut and solder the wires together matching the colours? The wire attached to the 02 sensor is much thinner than the wire hanging from the old plug.
Huffer
11-13-2009, 10:17 AM
It's a cheap sensor... don't even bother. If you do cut the wires and solder them together, you'll lose your factory harness plug.

Better idea is to go buy a proper fitting sensor with the correct plug. It's likely that that sensor is toast with the car being in limp mode for 3 years.
jey
11-13-2009, 10:39 AM
The 2nd O2 sensors after the cat won't put the car in limp mode. But it'll throw a CEL no doubt.

+1 on getting the proper sensor. Splicing might work but who knows what condition that O2 sensor is in.
dereku
11-13-2009, 11:41 AM
It's a cheap sensor... don't even bother. If you do cut the wires and solder them together, you'll lose your factory harness plug.

I wouldn't cut into the car harness. The plug for the old 02 sensor is still in it, like the cut the wires to get a socket on it the 02 sensor, and left the plugs attached.

Good to know it is a cheap 02 sensor. I might try it just for shits and giggles next time I am under it to see if it works. The problem is I think two of the wires are both white, without another trace colour.
jey
11-13-2009, 11:56 AM
Good to know it is a cheap 02 sensor. I might try it just for shits and giggles next time I am under it to see if it works. The problem is I think two of the wires are both white, without another trace colour.

That's ok, the white wires are for the heater circuit, and there is no polarity so you can't get it wrong.
dereku
11-13-2009, 12:07 PM
Perfect! I will post up how it goes. Thanks a lot!
dereku
11-13-2009, 02:06 PM
Disconnected my battery, tried to solder the wires (they wouldn't take for some reason) so I used butt connectors and heat shrink overtop.

Started up the car, and it runs fine. Check engine light is out for now, but I haven't taken the car for a drive yet, it has just been idleing for about 5 mins.