The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

OBD I Code 2-1-2 Woes 200 1991

I few observations/questions:
Why did you replace the head gasket? Was it leaking coolant or oil into the exhaust which contaminated the O2 sensor?
If the ECU goes to "open loop" then it cannot find ANY O2 signal! You should be able to check this by putting a VOM on the O2 wire and see a steady voltage, which is the voltage the ECU puts out with no O2 sensor attached, about .592 volts I think.
Otherwise, you should see the varying O2 output voltage, most readily seen with a scope, but a VOM will show the voltage varying from about 0.1 to 0.8 volts. Pretty sure if you check the 700/900 FAQ you'll find this test for the O2 sensor.
I would do the tests on the O2 sensor, and if it fails those tests, replace it.
I have used the universal replacements. The only difference is they have to be wired into the harness (only 3 wires) presently on the car.
--
744 & 745 GLE's (IPD a-sbars)16v M46, 245 SE(IPD a-sbars) auto, 242Ti M46(IPD springs and bars), 745GL 8v auto






USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.