Author Topic: O2 Sensor test- is mine in or out of spec????? (Read 3237 times)

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.

eric16v · « **Reply #1 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.

longtallsally · « **Reply #2 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.

4banger · « **Reply #3 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

longtallsally · « **Reply #4 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+).

4banger · « **Reply #5 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.