O2 Sensor connector

[DRACO A5OG]

If it has the same connector as the 3.2 84-85

[devinbholmes]

Louie - Sending you PM as well but I could use 2. Can pick up since I'm in the SF area as well. Thanks!

[911tracker85]

resurrecting this, just PMed Louie.

hoping he is still making these. trying to remove O2 to pull the engine tin for valve adjust.

desperate.....

[DRACO A5OG]

I am sure he does.

[911tracker85]

yep, got a PM back that he is making some more. just read through this to confirm I can cut back the shielding and just crimp the connector to the internal wire.

now to be patient for Louie85 to get it to me.

[PushinRice]

My connector is also not looking good. I have a PM into Louie85 about the connector.

[PushinRice]

Another pic, can’t tell if the wire is damaged or not

[mark944T]

I'm in the same boat and wondering if it works for a 1980 SC. I'll PM Louie.

[spuggy]

Originally Posted by Gogar

I don't think I understand why you don't just snip the green wire out of the old connector and solder/connect it directly to your new part, though.

This has actually been covered on this forum before...

Bosch (who actually invented the automotive oxygen sensor), needed a source of reference air for the oxygen ion pump in order that the zirconium dioxide cell had something to compare against the exhaust gas... (yeh, these things are a solid-state electrochemical fuel cell, pretty amazing for the 60's).

A Bosch sensor is 100% sealed - absolutely airtight, by design. They don't take reference air via the sensor body - because road dirt buildup on the sensor could block the air path without which the sensor can't/doesn't work.

The source for the reference air is instead down the the stranded wire in the harness. It only needs a minute amount.

If you solder the connectors, or decide the harness would look nicer with heat shrink over it, you cut off the path for the reference air.

Which is why Bosch sensors come with a pre-attached harness, and why multiple application notes over the years have explicitly stated not to solder the connectors.

If you look at the picture for the universal replacement sensor on Bosch's web site https://www.boschautoparts.com/en/auto/oxygen-sensors/premium-oxygen-sensors-with-oe-smartlink, you may note the provided Posi-Lock (crush-type solderless) connectors...

e.g. from p30 of http://aa-bosch-ecat-ap.resource.bosch.com/sao_ecat/downloads/Bosch%20Australia%20Oxygen%20Sensor%20Catalogue%20 2013.pdf:

As the sensor receives reference air through the connection cable, the use of cleaning/greasing fluids at the sensor plug connection is not permitted.

It's probably also worth pointing out that a single-wire O2 sensor also relies on a good electrical ground via the sensor body where it screws into the bung to complete the circuit. And by extension, through the headers to the earth strap.

I'm a little bemused why the topic of extending the life of these sensors keeps coming up. They're wear items like spark plugs and filters. Many things can hurt them - like thermal or mechanical shock, leaded fuel etc.

The folks who designed/make them say

Oxygen sensors should be checked and/or replaced at -
50,000 km for single and two wire sensors.
80,000 km for three or four wire heated sensors.
160,000 km for planar type sensors

They're pretty easy to check with an oscilloscope - but If you have a system that relies on an accurate lambda signal - i.e. for closed loop operation - then you need a good sensor, otherwise the motor won't run as designed.

[cnielsen]

Any more of these available?

[jfawsitt]

I'd like to purchase one of these.

Thanks,

JF

[Myami]

PMed to order a couple.

[Kerschbaumer]

I have same problem, anyone know if these are still available? PM'd Louie but havent heard back yet. My plug is hanging on by a bare wire.

[arbita1]

Originally Posted by Kerschbaumer

I have same problem, anyone know if these are still available? PM'd Louie but havent heard back yet. My plug is hanging on by a bare wire.

Here is where I got mine if you need another option.


https://www.kroonwireharnesses.com/index.php?route=product/product&product_id=747&search=O2+


Sent from my iPhone using Tapatalk

[Kerschbaumer]

Great - thankyou - I am looking into it, so far their shipping quote is for 80 Euros!

[arbita1]

Originally Posted by Kerschbaumer

Great - thankyou - I am looking into it, so far their shipping quote is for 80 Euros!

They have a cheaper option. Email them.

[Quasimoto]

Looks like a common problem...guess I’ll be machining up a new one.

[isby]

After reading this old thread, I’m beginning to wonder whether my DIY fix of this connector last year (solder + heat shrink) is the cause of my idle problems. PMed Louie to see if he has any more connectors, but haven’t heard back yet. Has anyone come across a cost effective replacement connector? Thanks.

[GH85Carrera]

From what I learned back when I bought one of the replacements, that connector is common to BMW, VW, Mercedes, and of course Porsche of the same era. If you have a good parts guy from other German makers they sell the same connector to the harness. They all break after 30+ years if the car is driven much at all. They plastic yellows and get brittle.

Just like the flywheel sensors for a BMW work perfect on our 911s, that O2 sensor connector is the same part, just finding the source is the hard part.

[scarceller]

If you fix this connector you MUST be aware that the wire is a shielded line. It has a center conductor that's the actual signal wire. But it also has a outer braided shield wire, if you accidentally happen to solder the shield to the conductor or they touch in any manner then what this does is grounds the signal line. If the signal line gets grounded it drives the signal to 0vdc this causes the DME to see and think that the mixture is lean and all hell breaks loose! The DME thinks the O2 sensor is sending a lean signal and the DME now starts to richen mixture and it will go super rich!

Be very careful fixing this O2 signal connector.