Oxygen Sensors replacement

[StartX5]

Hi everyone -
I am going to replace my X 4 O2 sensors sometimes next week (ordered 4 pre/post Bosch sensors).
How difficult to remove and install them for the 3.0 engine? If you have done this before, please share your experiences!

Thanks alot!

(I have PB Blaster spray and 22mm sensor socket tool and other general tools).

[StartX5]

Done in 2 hours. Postcat O2 sensors gave me big time to locate and removing them, and i was like a mineral worker since i did not lift the X5. If you need DIY photos, i will post them later.

[SlickGT1]

Deff throw up a DIY, it never hurts. Glad you got it all taken care of.

[Lin]

please post DIY and pics with with links to where you bought the sensors too.

[StartX5]

sorry - my little daughter messed around my powershot camera, she deleted half of O2 Sensor DIY photos, and i am unable to complete DIY photos thread here. If you have any questions regarding the O2 Sensor replacement, PM me.

[sah62]

I just did all four sensors on my daughter's 2002 3.0. We bought the Bosch sensors (13477 upstream $49.79, 15109 downstream $57.79) from RockAuto.com. Doing the job requires removing the front end reinforcement plate to gain access to the downstream sensors. The six self-locking nuts and bolts used to attach the plate are one-time use only, so those needed to be replaced, too. I picked them up at our local dealer. The upstream sensors were easy, but the downstream sensors were more of a challenge. Here's the basic process:

1. It will likely help to soak the sensors with a penetrating oil like PB Blaster. Oxygen sensor sockets (7/8" available from your local auto parts store) are slotted on one side to allow the wiring to pass through. That's great for fit, but it also means that the socket can slip a bit (and possibly round off the hex nut fitting) if the sensor is in really tight.

2. Remove the intake manifold cover from the top of the engine. You can disconnect the downstream sensor connectors once the cover is removed. Don't do anything else with those wires yet.

3. The two upstream sensors can be found on the right (passenger) side of the engine. Disconnect the wiring and move the connectors out of the way. Soak the sensor fitting with penetrating oil. Give it time to work. Remove the sensors using the socket and extensions. Installation is the reverse of removal. The sensors come with anti-seize on the threads - don't add any more. Torque to spec (50 Nm or 37 ft-lb) and reattach the wiring.

4. Now comes the fun part. Jack up the car to gain enough clearance to work underneath. Support the front end with jack stands.

5. Remove the front end reinforcement plate. You'll need to remove two small screws from the front of the plate and six bolts, three on each side. You'll need a combination of 17mm wrenches, sockets, and extensions to gain access to each of the nuts. Hold the nuts and remove the bolts from the bottom. An air ratchet made the job a little easier for me. Toss the nuts and bolts when done.

6. The sensors should now be visible near the catalytic converters on the right (passenger) side of the car. Soak the fittings with penetrating oil and give it time to work.

7. I wasn't able to use my sensor socket on one of the sensors because I couldn't attach a wrench on top of the socket once it was in place. A 7/8" open end wrench did the trick. Remove the sensor and let it hang.

8. Remove the second sensor with the sensor socket. I had some trouble with this one because it was in tight enough that my sensor socket started to expand and round off the edges of the hex nut on the sensor. I had to cut the sensor in half and use a deep 7/8" socket to get it out.

9. By now you may have noticed that the connectors for these sensors are on top of the engine, the sensors are way down here under the car, and there's not a lot of room to just dangle the new sensors over the back of the engine. I was able to run the wiring by securely taping (I used masking tape) the connector end of the new sensor to the sensor end of old sensor and then gently pulling on the old wiring from the top of the engine. Do one at a time, and be ready to move back down underneath to free the wire from any obstacles. Pull gently!

10. Once you have the new connectors on top of the engine you can start to button things back up. Go back underneath the car and install both sensors. Torque to spec (50 Nm or 37 ft-lb).

11. Reinstall the connectors on top of the engine. Return all wiring to it's original holders. Start the car (but DO NOT drive it) and make sure there are no warning lights. Turn the car off. Reinstall the intake manifold cover.

12. Go back underneath and reinstall the front end reinforcement. At front, make sure to install the support under the plastic trim piece. It helps to install the rearmost nuts and bolts first - those nuts are the easiest ones to reach. Make sure that you reinsert the bolts through the sway bar mounting brackets! Torque to spec (56 Nm or 41 ft-lb) and then turn the bolts an additional 90 degrees.

13. Remove the jack stands and lower the car. Done!

It took me about five hours to do the job. Most of my time was spent under the car.

[Blowout]

Just changed out the upper O2 sensors. Easy access. The Bosch electrical connectors were a little different than the OEM so it was a tight fit getting them on. Seems Bosch didn't cut the interlocking groves on the sides as the OEM sensor. I used sparkplug boot grease to make the gasket material slip in easier.

Had a code E10 showing before the change (O2 sensor, bank 1). Now to see what the wife says after driving it. I'll check the codes again tomorrow to see if it went away.

Thanks for the write up!.