help with testarossa o2 sensors please!!!

The two pin connectors are just a +12V power and a ground for the O2 sensor internal heaters -- it doesn't matter which is connected to which.

The single wire with the female spade terminal is the active output for each O2 sensor:

the single wire from the O2 sensor in the 7-12 bank exhaust stream should be connected to pin 8 of the forwardmost injection ECU

and, likewise

the single wire from the O2 sensor in the 1-6 bank exhaust stream should be connected to pin 8 of the rearward most injection ECU

Unplug the 25-pin connectors at the injection ECUs and use an Ohmeter to make sure you've got this correct.
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I checked the O2 wire in my '87TR and it was the opposite of what you said. I swapped the O2 connectors and the car wouldn't idle. Are you certain the 1-6 (passenger-side) bank goes to the rearmost ecu?

 

My TR must live in a parallel universe.

 

I would like a confirmation of that as well. I suppose it is possible that the wires were mixed up and the CIS was adjusted to fit, I suppose.

Is it so that the car will not idle correctly if the O2 sensors are mixed up?
Should the battery be disconnected then reconnected? - Steve?

 

Fairly certain, but two points:

1. Let's confirm whos' who -- by "forwardmost" I mean the one physically mounted the furthest forward on the chassis (not the one closest to you when you stand at the back of the car). If we're not in disagreement there,

2. As long as the O2 sensor, Airflow Meter Potentiometer, and EHA from the same bank are hooked up to the same injection ECU, it wouldn't know the difference (I'm not sure if this is, or isn't, physically possible with the harnesses). For the "stock" arrangement, the two wires going to each EHA on the FD would be the following colors:

1/6 bank = yellow and yellow with black

7/12 bank = grey and grey with black

Are yours reversed from that?

 

I'll check in the morning.

 

Yes, this would be bad for warm idle (closed loop) -- for cold idle (open loop), it wouldn't make any difference.

No difference, the TR injection ECUs aren't that "smart" and have no "memory".

 

I was under the impression if you reversed the O2 plugs the engine won't run properly ie; one side runs lean the other rich. The ECUs aren't sync'd to the O2 readings.

 

I spoke a little too soon. Checking the color code to the EHA's is not easily accomplished.

 

You got that right. I think you need to remove the upper intake to do it, else I don't see how you could ever work back there.

 

You guys are making this way too hard. Open the rear bonnet and look in from the RH side around the cyl #1 intake runner -- you should be able to tell if the wires going to the 1-6 FD EHA are light (yellow) or dark (gray).

 

Yep. There was some tape on the wires, but Steve is right again. Yellow.