ford o2 sensor for 3.2, which wires are which...
 

i'm flying back to ohio next weekend to drive my 911 to florida, i picked up a Bosch 13953 o2 sensor and will be splicing/heatshrinking it to the porsche wiring.
there are 3 wires, 2 white/1 black.
the black is ground, one white is for the heater element, the other is the output feed to the dme.
how do i check which is the heater wire and which is the output?
thanks

Bell,

Search the threads and you'll find more details, but the black wire is DME reference. The two white wires are for the heater element in the sensor and are simply wired to either white wire. Just did mine a couple of weeks ago. Get some heat shrink and a decent soldering gun. And stagger your connections. I did mine all the same length and it ended up bulging quite a bit inside the sheath.
Drive safely!

I'd be leary of using other than stock O2 sensor. The connector supplys comparison atmospheric gas to the the gas sensor

If you want to be 100% sure, put an ohm meter on the 2 white wires and you should get a reading for the heater element. maybe few hundred ohms. the black wire will give you no readiing either to the case or to the white wires.

You can also check that you hook the white wires to 12 VDC. Check the voltage coming in.

Soldering is the way to go.

O2 sensors put out 0 to 1 vdc depending on oxygen present. they all put out in the same range. Ford or Bosch does NOT matter as long as they are both good qulaity.

got it, the ford sensor will work fine for the trip, ill be replacing it with the proper one after im settled. thanks guys :)

I've had a generic sensor for several years, with no problems. The car has passed smog inspections twice (maybe three times) since I installed it, and runs very well.

The two white wires are for the heating element. Just connect the white wires on the sensor to either white wire from the car. Connect the black wire on the sensor to the black wire on the car. I put a small piece of heat shrink over the connection on each wire, and then a larger piece of heat shrink over the bundle.

Good luck!

I installed a generic O2 sensor and first tried to solder the wires but couldn't because the wires were stainless and the solder wouldn't stick.

So I had to use crimp on connectors, 3 wires which required 6 crimps and it looks messy.

Next time I will use a plug in Porsche sensor.

I am an Ex Bosch Automotive instructor. First White is heater and Black will be sensor wire. The sensor is a sensor same as any non wide band sensor. the heating element could throw codes but that will be mostly on your OBDII cars. Soldering is the NOT way to. The sensor needs reference air and it gets it down the wire on all bosch sensors. If you solder it you have a chance of sealing off the air.

Interesting. Please elaborate. I'm having trouble understanding how the black wire does anything more than conduct the signal from the sensor itself.

from all the research i've done on o2's over the past year what happens is the dme get's it's ambiant air reading (as opposed to inside the exhaust) from the air in the sensor wire itself......
some of the sensors have a tiny opening on the sensor where the wires come out, some use the wire......
there was a good thread on the subject where we all thought it was BS, but turns out we were all wrong :D

here's the thread, there's a few photos on the last page of the small inlet
http://forums.pelicanparts.com/porsche-911-technical-forum/78442-o2-sensor-alert-new-info.html?highlight=oxygen+sensor

thanks for the help guys, i'm next day airing a box of tools, parts,etc for the drive home wednesday, it'll meet me in ohio when i get there friday.....don't want to even try to take that stuff on the plane, only thing i'm taking on the plane is some clothes, my sirius stiletto, and a toothbrush.....not even messing with luggage :D

Regardless if it is a Planer or a thimble type sensor it has to get reference air to the reference air chamber. The sensor works like a galvanic battery. The oxygen ions move threw the zirconia ceramic crating a voltage signal 0-900mV with Lambda being 450mV. Outside (ambient) air works its way down the sensor wire to fill the reference chamber. So when the Lambda is less than 1 (rich) there is more less ions in the exhaust flow so the reference air moves to the exhaust side creating higher voltage 450-900mV. Kinda like the chemical reaction you get from when you place a load across a battery. When there is more air in the exhaust stream Lambda greater than 1 (lean) there is less movement of ions creating less voltage 0- 450mV.

The sensor needs the ref. air not the DME. thats how the PFM takes place;)
there are some MFG that had a hole ast the top or the sensor to let ref air in.

I read somewhere that most of the wire insulation used on the O2 sensors is intentionable made with leaks enough to let the reference air into the sensor and then there is the tiny hole in the ceramic on the generic sensors.

I have used generic Porsche sensors on my 964 for the past 5 years and never had a problem.

Ingo

you're right.....i never said i was an expert....i was thinking backwards :D

plus 1 or 2 (whatever) on the generic. Bosch makes it for Ford and it's half the price. Works for me.

A. I soldered my wires
B. I put heat shrink on each solder joint.
C. I put heat shrink over the entire bundle of wires.
D. I have passed California smog tests several times since replacing the sensor with a generic one.

I have to believe that my sensor is either getting air from someplace other than than the wires, or that the heat shrink tubing is somehow allowing air into the sensor.

The bottom line is that my car runs great with a generic sensor with soldered wires.

sensor air! Ah can I make an air scoop and force more into the sensor and make more HP?

I thought I knew a little bit about O2 sensors....guess not.

This is the easy one, you see how a wideband o2 works.