M42 o2 Sensor - Where to buy?

[KenC]

I know a lot of guys with M20s use Mustang O2 sensors and just solder the wires with the stock connector.

Is there a universal M42 O2 sensor?  Or where is the cheapest place to get an OE one?

[P. Kennedy]

...Pelican lists a couple of different O2 sensors for the E30 318is, one of which is only $87.  They also list one for around $130 which is also BMA's price.  I don't want to spend three figures if I can help it, but I need a new one.

[P. Kennedy]

I misread the Pelican online catalog.  They list one for the '91 318is for $118, which is still too much, but I may have to bite the bullet.

[hoevesruperd]

someone told me earlier on this forum that a bosch universal is a cheaper replacement
i think it consist of only the sensor that you connect to the old cable and plug
but i dont know where to get it or what part number it'd be

also interested in this, as i'm getting about 8mpg. (yes, its actually cheaper to run a tubo'd S54)

[Wise Old Dog]

8mpg, that sucks, you can probably see the gas coming out the tail pipe. No way is it burning it.
I have a universal Bosch. It's been a couple of years, but I think you just buy it according to how many wires it has, and then splice it. Thats what I did. I'm getting great mileage around town 27mpg, no highway miles.

[KenC]

8mpg, that sucks, you can probably see the gas coming out the tail pipe. No way is it burning it.
I have a universal Bosch. It's been a couple of years, but I think you just buy it according to how many wires it has, and then splice it. Thats what I did. I'm getting great mileage around town 27mpg, no highway miles.

Where did you get the universal bosch one?

[bmwman91]

ANY 4-wire oxygen sensor will work, and if you are clever with wiring diagrams, so will a 3-wire.  All narrow-band O2 sensors put out the same signal.  If having the plug-n-play connector is worth an extra $80 to someone, go for it.  If you want to do a little soldering & heat-shrink-tubing, save yourself some $$$!  I can post up some wiring diagrams if needed.

[jrobie79]

id be interested in those wiring diagrams, where can i get the cheapest universal O2 sensor, either 3 or 4 wire, my dads an electrical engineer im sure he can figure out some way to wire it up or the diagram will help

[parker575]

Please post wiring diagrams and where I can find a standard 4-wire 02 sensor.

[Wise Old Dog]

IIRC I got it from an e-bay vendor and the instructions for the color coding are in the box. I figure somewhere on the web, there are numbers listed for the parts. Or the local  parts store might have some info.

[parker575]

found one on ebay for $27 shipped.

[bmwman91]

Hokay.....

Relay circuitry:


The O2 sensor itself.  The sensor has a black, white, and 2 gray wires coming off of it.  I cannot remember which is which,  so just match their position to the connector pin #'s in the diagram when you look inside the connector body.  Simple enough!

[bmwman91]

THAT is why I recommend the Chilton's guide over the Bentley for the E30 318iS.  It has this stuff at half the price.  I have both manuals, and the Chilton's is every bit as capable with regard to this car (others not so much).

[parker575]

Installed the new o2 sensor. Spliced the wires and it works perfectly. My old one came off fairly easily, and it was pretty black around the base of the sensor but was white on the top. The car is clearly running better, however I don't think my mileage is back. After 65 miles the gauge is just under the 3/4 full mark. Is that normal? Should I run it through another emissions check to see if the hydrocarbons came down? Is there a chance I have an ECU issue?

[teh Phil]

Would this one work, or should I go for a more expensive one like this one or this one? 25 bucks seems a little too cheap for an O2 sensor! :eek:
-Phil