What heated o2 sensor do I need to get correct readings for tuning with a scanner? Would a 3 wire heated o2 from a fullsize '95 chevy truck with a 4.3 liter V6 work? If so, I have a new Delco heated o2 from my truck listed above. If not, I will get the best one that you guys recommend. With my single wire o2 now located in the y-pipe, car isn't going into closed loop for me to get readings to tune by.

Thanks,
Mike (1bad91Z)

 

'92 Astro van vin code "Z"

 

Ok, on a 3 wire '92 Astro van Z code heated o2, there is one black wire and two white ones. Which one is ground, power, and ECM signal wire? A picture would be GREAT if possible!

Thanks again,
Mike (1bad91Z)

 

I just installed a 3 wire o2 in my TPI Gmc truck, it works great! The black wire is the computer signal wire, the other two white wires are for the heater, one + one -, it doesn't matter which one is which.

 

It doen't matter what white wire is power or ground? That doesn't make sense?

Craz28 - did you use the 92 AStro van o2?

 

That is correct. It does NOT matter which wire is power or ground. The white wires go to power and ground (doesn't matter) and the black to the signal.

Tim

 

yes, i used one out of a 92 astro, I used a matching connecter from the wiper motor harnness of a 3rd gen firebird and it plugged right in to the O2. works great

 

Take a 12 v light and hook it up backwards,it works.
Anything that makes heat is a controlled dead short therefor grounding a power wire so if you reversed continuity it would make no difference its stilll a short.