Solder or Solderless connections?
 

Which do you guys prefer? Either way, I usually follow up with shrink wrap tubing. I'm going to re-do the 3-wire O2 sensor that a Porsche repair shop broke on my 911 last summer.

Thanks!

It's pretty tight in there I soldered the metal mesh sleeve then heat shrink wrap. But the actual connection, I used crimp on insulated ones.

The shield is the most important part because it can send errand signals to the DME.

In my experience, the wire attached to an O2 sensor is steel and un-solderable.

oooh. Great info, guys. I was planning to take the whole thing out and solder it at the soldering station. But it sounds like I'm going to use solderless, perhaps with an overlapping joint with either copper or gold. I think the reason the car started running funny is that the joint cracked and is loose. It looks like the old solder stuck to the wire, but the tight access made them glop the stuff on carelessly.

Just insure the metal mesh shield is insulated by heat shrink wrap. Sorry to be broken record. This caused me so much grief until we fixed it.

I just jumped out of bed to look at the connection. There is a crack in the yellow plastic. I wonder if that is causing weird signals to be sent to the dme? I don't see the metal mesh shield, but I'll take everything out, and then I'll see what you're describing.

Thanks a million Draco!!!!!!

Ha, I was thinking about this last night as I was falling asleep.

Anyway, I think I understand the "wire mesh" is in the insulated sleeve that is shaped like a drinking straw, right? I was wondering what that was for. There is wire mesh shielding both above and below the engine tin.

Right now, I'm thinking about the engine harness side of the connection. Here's a picture of the damage done by the shop:

I'm thinking about sanding off the crumbly bits, and JB Weld on the yellow plastic. There should be a way to check if the wire has a break in it, right? Should I disconnect the dme harness, and try connecting a battery to the wire, and check the voltage on the other side? (Sorry, at work now, do not have Bentley with me at the moment)

Thanks guys!!!

Drago, you're really putting a lot of magic back into the Kharma bank!

just adding links for future reference:

http://forums.pelicanparts.com/showt...=sensor+repair

http://forums.pelicanparts.com/showt...hreadid=221966

http://forums.pelicanparts.com/showt...hreadid=389508

Oh Damn. the mesh will be underneath that yellowed housing and green wire cover (use to be white but heat discolored it and made it brittle). The shop may have damaged the wire.

Just use a plyer and crumble away that thing, check the wire for cuts (solder here for extra measure of assurance), if good, place shrink wrap over any exposed mesh, cut the OEM bullet connector off then crimp on the insulated spade connector.

On the O2S side, cut the rubber connector off and crimp on the mate insulated spade.

That's it Brotha!

Note if you can buy quality male and female insulated connector, do so. I used cheap Home Depot special but no issue they worked fine but if I had time I would have paid more for Brand name. Will update later when I have to replace the O2S for maintenance.

LOL, You started it by helping me in the past. Just paying you back the best way I can. Thanks again :thumbup:

IIRC, I was able to solder mine. I then used heat shrink on each individual wire, and then a larger piece of heat shrink over all of the cables. It's been several years and it's working fine.

Thanks Draco and Scott!

It's reassuring to know that others have repaired this without problems. I agree with breaking away the plastic connector because the harness wire is so short. I think I'm going to see what is available at Home Depot as well as my favorite hardware store here in town. But before doing anything, there is a automotive electrical shop that I'll probably eventually buy an insulated connector from. They are called Electric Laboratories and they have sold me many nice relays, batteries, etc.

Thanks again guys, I really appreciate it.

This is for future thread searches:

"Repair Oxygen Sensor Connector"
"Oxygen Sensor Replacement"
"Generic 3wire Oxygen Sensor"

I can't really understand why, with the high $$$$$ amount for these and other German made luxury or performance cars, why the manufacturers would use such crappy plastic in the O2 sensor connectors. I know from personal experience, that the same type of BS plastic connectors are also used on BMW, MB, and Porsche, O2 sensor equipped vehicles. The connectors just seem to fall apart, with the slightest touch, let alone trying to unplug the connector fittings. This is not just on the older models, it is that way on some of the vehicles from the late 90's up through some of the 2000+yr models as well. Nothing like having some kind of crap connectors that probably cost about $0.15, to cause so many problems. Good luck!! Tony.

I would look for a replacement. Unless you just want to kill some time, but it may benefit to just replace it. The voltages generated by an o2 sensor is small and they are sensetive to connections-soldered or not. I know it has been done, I have even done it, but a new sensor is the best way to go.

ok, checking back in. The sensor wire solders very nicely. The heater wires do not want to solder at all. Maybe I need to use silver or something other than lead, because whoever installed the O2 sensor was able to solder it. However, the solder broke off, which created problems.

I used crimp on connections on the heater circuit, followed by shrink tubing, then followed by the mesh shield tubing. I hooked it up, and the heater circuit is working fine. Have not tried the sensor yet, as I am still repairing the sensor connector.