4 wire heated O2 install gone wrong

[USSkoval]

This is very frustrating, it seems there is no info on installing the 4 wire O2 sensor anymore, just the 3 wire. Because of this, I hooked up the wiring based off my memory. Well, I caught the O2 sensor on fire

Can anyone please tell me what I did wrong? There were two brown wires, which I thought were both ground. There is the purple wire, which I know is the signal wire. Then there's a tan wire that I thought was power for the heating element.

I used a sensor and pigtail from a '00 Bonneville because they were free. Of the two wires that I thought were both ground, one goes to a black wire in the pigtail, while the other goes to a pinkish one. Is one supposed to be power, and the other ground? If so, what the heck would the tan wire be used for?

 

[Russell]

What is the make and part number of the 4 wire sensor?

 

[USSkoval]

I'd have to check on the part #, but it's an original GM (AC) sensor installed when the car was new. I can't use it now though, I'll have to buy a new one.

 

[sweetk30]

just buy a 3 wire.

http://www.tbichips.com/faq.htm read Q2 its got the gm #

 

[bp71k5]

Here's a reference to doing something similar with a different vehicle:
http://www.v6z24.com/howto/o2heated

In the TBI harness, anything connected to a pink or red wire is usually hot (+12v) so if you connected the O2 ground to any kind of pink wire, that's probably why it fried.

I also just ordered a 3-wire for mine. The 4-wire appears to only be useful for TPI style injection where a dedicated ground signal is required.

 

[USSkoval]

Thanks, I had two wires backwards. I got a new sensor, so I'll switch the wires around in the harness I made and try it again.

Oh, I used the 4 wire sensor because I already had it and the connector. The new sensor I bought is also a 4 wire because I don't want to buy/find a 3 wire pigtail to use.

 

[USSkoval]

Ok, install complete and everything seems to be fine (no fire). This time there is an inline 10 amp fuse.

 

[Russell]

Good deal