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DISCUSSION => Engine management => Topic started by: longtallsally on March 04, 2010, 10:59:21 AM

Title: O2 Sensor test- is mine in or out of spec?????
Post by: longtallsally on March 04, 2010, 10:59:21 AM

My fuel mileage is OK, not great, but OK at ~24mpg in mixed driving.  Wait, who am I kidding, I'm in Germany, I'm either going 80 on the Autobahn or in very tight city traffic.  I've never once seen this elusive 35+mpg that many around here tout to get.

Anyway, on one of the million manuals that I downloaded from this site, I found some procedures for testing the O2 sensor.  It says on the ground (black) and grey wire, the signal should fluctuate between .2-.8v.  Mine was hovering around .65-.7 and then would drop off and come back again to .65-.7.

Then I did the resistance test for the heater element (the 2 white wires).  According to the regular E30 paperback Bentley the resistance should be under 5 ohms.  I got a reading of 6.

I've never seen anyone mention these values in any of the searches I did and my results leave me in a quandary.  Is the sensor bad or not?

I'm surprised that no one has mentioned these tests as they take less than 5 minutes and you don't even have to get under the car to perform them.

Title: O2 Sensor test- is mine in or out of spec?????
Post by: eric16v on March 04, 2010, 04:21:52 PM

not sure about the test. What are you doing in Stuttgart? Thats a fun city. Spent some long nights there as I have some family in that area.

Title: O2 Sensor test- is mine in or out of spec?????
Post by: longtallsally on March 04, 2010, 04:52:38 PM

Quote from: eric16v;

What are you doing in Stuttgart?

Wondering if my O2 sensor is bad. :)

My wife- and now I - have gigs here. Going to hang for a couple years, get all the cool "Euro" parts everyone drools over and come back to CA.

Title: O2 Sensor test- is mine in or out of spec?????
Post by: 4banger on March 05, 2010, 02:05:22 AM

speaking of euro parts. id allmost sell a kidney for a set smiley lights. a set o 16in 3peice basket weaves and one of those cool boot spoilers that the euro's had on the 318 4 doors......bastards lol

Title: O2 Sensor test- is mine in or out of spec?????
Post by: longtallsally on March 05, 2010, 05:01:25 AM

'Preciate all this, guys. But looking for some help on the O2 sensor. :)

On Euro parts, don't get too riled up- parts are actually more expensive here than in the states- including OEM. The only benefit is that they are easy to find. Although I think I can get a set of regular smileys for $50 (the smoked are still 3 bills+).

Title: O2 Sensor test- is mine in or out of spec?????
Post by: 4banger on March 05, 2010, 03:47:50 PM

man i you find a set of regualr smileys for $50 pick those bastards up and hang on to them. i will gladly make it worth the effort.