Well since I've got headers in finally I'm switching to a 3 wire heated O2 setup and was wondering if anyone had any tips/suggestions to go with it? TBI Chips just says purple wire to computer and the others ground and hot, he recommends a relay and fuse to go with it. The fuse isn't a problem but what kind of relay would I use in this type of setup if any?

 

I just used one of those 30amp type relays you buy for hooking up lights with. about10 bucks for the relay and socket. Wiring is pretty straight forward. then just run a ground lead to the back of the head.
You might try running the single wire first, I am running block headers and have no problems with the sensor getting cold.
I thought I had a problem since the system went open loop at idle, turned out that it was programed into the ecm to go open loop below 950rpm.
expensive mistake to make considering that the heated O2 is almost 80 bucks. and the single wire is only 30 bucks.

 

Last night I hooked up the single wire, it was originally just sitting in the bung to block the hole since it didn't have enough wire to reach it's new location. Just had to extended it a bit. Not sure how well it is working the readout sort of bounces up and down (did this before headers too), though I don't have a clue how it is supposed to look on the WUD.

 

If you are seeing voltage fluctuations going up and down the scale then it is working. Not usre of the voltage readings but I do know that it will go up and down once the O2 reaches operating temp.
Sounds like it is working fine. Now you just need to hook up the laptop and see if it is staying closed loop..

 

I tied my power wire into the fuel pump wiring. It ran right by the O2 sensor and is only hot while the engine is running.

3 Wire Heated Oxygen Sensor Wiring Adapter

 

That is a nice setup, I might just spring for it though I think I'd have to extend a few of the wires.

 

I did the same thing as Fast355 did... hard wired it into the fuel pump wire with its own fuse. Mine was 4-wire, but I recommend a 3 wire for the ease of install.

 

Is the connector designed for the S10 O2 sensor that is recommended on tbichips.com?

 

I am glad I found this thread. I put a new bosch 02 sensor in my car, 89 305 TBI. I was watching the O2 switching on the scanner and good lord it switches slow. Are all TBI's like that? I have no cat. Is the o2 not heating up? It goes into clsd loop, but still switchs slow as heck. would a 3wire be benifical to fuel mileage

 

Tier............the o2 is supposed to "bounce" up and down. What kind of readings come across the WUD for INT and BLM? Those are the end results of the o2.