Lambda sensor wiring

[sam3007]

I am looking for a bit of help getting my 86 running a bit better. It is running very rich currently which I think is because the lambda sensor currently isn't plugged into anything.

However there doesn't appear to be a plug on the main loom to plug it into, either I am being an idiot and just can't find it. Or it could have been cut/removed for some reason.
Could anyone help me with a picture or video of where the lambda sensor wiring should be on the main/engine loom?

I will attach a picture of my plug on the current sensor

It's a zenki 84 Japanese model if that makes any difference
Thanks

[Project D]

Wrong sensor ?!
On all the AE86 I worked on, those who had a lambda sensor (from factory) where all a one wire sensor.

[banpei]

Indeed. It should look like this:

Maybe they installed a random sensor?

[Power_uP]

I've seen a few imported 86s with cat wires that go absolutely nowhere, so you don't have anything too unusual. I doubt that's the cause of the problem.

[The Doctor]

In Europe, most very early map 4age engines don't even have an o2 sensor, only some sort of basic Co adjustment screw. Don't know about the Japanese models, but it might be the case of an aftermarket exhaust which came with an o2 sensor from another car?

[banpei]

(05-11-2022 04:11 PM)The Doctor Wrote:  In Europe, most very early map 4age engines don't even have an o2 sensor, only some sort of basic Co adjustment screw. Don't know about the Japanese models, but it might be the case of an aftermarket exhaust which came with an o2 sensor from another car?

Correct, cat was available in Germany as an option starting with the facelift and Switzerland also switched fully to cat in early 1985. Naturally the Netherlands didn't care for the environment and we kept receiving cat-less cars.

[Bean]

cat was also optional in Switzerland, but many opted for it. My one is a late 85 (already face-lift) but without cat though (one of the last ones). More crucial we never received the Map version, all came with AFM and EGR. It's been such a long time but I think mine also never had a lambda sensor either due to no cat.

[sam3007]

OK well that's good to know I think! Atleast I don't have dodgy cut wiring to chase up.

I have a bunch of unused plugs in the loom above the exhaust manifold, so I expect one of those could be the original lambda plug. Is it worth trying to source the correct sensor? I imagine a one wire sensor isn't going to make a huge difference to the running of the engine?

My car does have a cat fitted, which I thought was a bit unusual for the age of the car.
It also doesn't have any sort of afm or maf fitted before the throttle body

Sent from my Pixel 4a using Tapatalk

[The Doctor]

If it has a cat I think it should have an o2 sensor.
And it's probably a map car, so somewhere on the bulk head should be a square ish little block with a vacuum hose attached.

[sam3007]

(05-12-2022 09:40 PM)The Doctor Wrote:  If it has a cat I think it should have an o2 sensor.
And it's probably a map car, so somewhere on the bulk head should be a square ish little block with a vacuum hose attached.

Thanks, yes you are correct with the map sensor.
I have attached a picture of the other sensor on the manifold, it's a single pin connector but I think it looks more like some sort of temperature sensor than a lambda?

I am currently making a decat pipe to replace the cat, I have a feeling the cat isn't factory so I'm unsure if it should/would have had one from factory    

Sent from my Pixel 4a using Tapatalk