I think I may have been sent a wrong part regarding the rear O2 sensor. Long story but here are the questions: The old sensor is shot and unusable. The new sensor has about 4 feet of cable when it appears I needed only 2 or 2 and a half. Can I still use the new sensor and temporarily take up the slack or might the new sensor send the wrong info to the computer? It appears my car has the rear sensor just in back of my "little cat" where as the new sensor may have been designed for a model needing more line, like a sensor downstream from the main or big cat.

Any suggestions? I am in a rural area and SOL at the moment. Thanks

Some folks have said that alot of auto parts stores have the wrong sensor for the 850's. Should be Bosch 12077864B00.

Most O2 sensors are quite standard, just the plug types that are different. Almost all current sensors have a sensor wire and heating element wires. Universal bosch sensors that you splice to your plug will work great as well. Rear and front O2 sensors have the same sensor just different wiring.

The cable length would not be an issue if it doesn't get snagged anywhere while you are driving - that is why it runs behind a shield in the original installation.

If you are not sure you have the correct sensor it may be that its electrical specifications don't match the original. The catalyst efficiency check is one of the ongoing monitors that depends on the rear sensor and it will fail if things are even a little off. That may result in a failed emission test, check engine light going on when there is no problem, etc.

I would recommend trying to find out if you really have the original type part or equivalent.

Thanks for the note! I did check w/ the store and they insist it is the correct replacement. They said the "long" line is to replace the existing connection below the ABS module and place it farther away from the rear of the engine. I have no idea what it would connect to or where that would be. Hence, I seem to have no choice but to connect the new long line to the old connector, leaving me with 5000 ft of extra line ;-). Something doesn't seem right.....

Sorry about the leaving out that the car is a 850 GLT turbo w/ 204K