Alfa Romeo Forums banner

1 - 8 of 8 Posts

·
Registered
Joined
·
298 Posts
Discussion Starter #1 (Edited)
My '84 Spider has been running really rich with oily black soot coming out of the tail pipe and thick black soot coating the plugs. I was ready to order a new Bosch O2 sensor for my '84 Spider, when I noticed that there are two extra white wires coming out of the factory harness that terminate in a female Bosch connector. I don't see these two extra wires offered on the O2 sensor for an '84 Spider at Centerline: O2 Sensor Early V6, Spider | Centerline International

Am I looking at the wrong item?

Thanks,

David

O2_sensor_IMG_7228.jpg
 

·
But Mad North-Northwest
Joined
·
10,537 Posts
Those are for the sensor heater. You need a three-wire oxygen sensor: it’ll have a plug for that.
 

·
Registered
Joined
·
298 Posts
Discussion Starter #3
Hi Gubi,

Thanks! So, it looks like I need to order the 02 sensor for the '86 model, not the '84 model, from Centerline:


Interesting that an '84 would have an '86 sensor...

Thanks,

David
 

·
But Mad North-Northwest
Joined
·
10,537 Posts
Dunno when they switched from one wire to three. If you're sure you currently have a three-wire, though, then it would appear that's what you need.
 

·
Registered
Joined
·
126 Posts
That looks very similar to the connections on the new 3 wire O2 Sensor I just installed on my '85 Spider Veloce. My guess is the 2 white wires are getting + and - from a nearby keyed source.

Why did I go with the 3 wire? I read on the BB that the factory 1 wire O2 Sensor doesn't work well when you replace the original exhaust with the 4 into 2 cast iron headers. Basically it takes longer for the Sensor to heat up meaning it goes into default mode sitting at stop lights etc.
 

·
Registered
Joined
·
298 Posts
Discussion Starter #6
Thanks for everyone's response. So, it seems like this will do the trick, even though it's not specifically for an '84 S3:


David
 

·
Registered
Joined
·
126 Posts
Here's a link to the one I purchased and installed a few months ago. Different part number but the Amazon version is cheaper and came recommended by others on this board. For me I had find a switch power/ground but since someone has already done it should be fairly easy for you. I've read you should try and keep the green wire as close to the original length as you can. That being said with my O2 bung being further away I did have to add a few inches. I like the posi-lock connector too.


Good luck!

C
 
1 - 8 of 8 Posts
Top