How-to Upper/Bank1 O2 Sesor Replacemernt W/Pics

Contour Enthusiasts Group Archives

Expanded upon from the original how-to, including pictures to follow along with the directions
(Original how-to located at: O2 How-to)

This is a How-to for replacing the Oxygen sensor (O2S) for the upstream bank number 1 (position 1). This applies to all Duratec 2.5 V6 vehicles. The location of this particular sensor is below a wiring harness below the coil pack. With the coil pack removed and the wiring harness out of the way, you can see this sensor on the exhaust manifold on the firewall side. You WILL be able to utilize a 02 socket for this job. This job took about an hour.

Bosch replacement part # 13115 (part # good as of 11-11-03)
Or you can order Motorcraft from Ford

Tools Needed:
1) 7mm Socket and 3/8â�?� ratchet
2) 8mm Deep Well Socket
3) 22mm Long Handled Wrench (or equivalent as per job) or 7/8 Wrench
4) O2 Sensor Removal Socket (Lisle PN# 12100 approx. $10 Sears or PepBoys)
5) Back-up curse words for the Furd engine design team.

This replacement is moderately easy with some patience and skinny arms/hands. There isnâ�?��?�t much room to work and not much room to maneuver the wiring harness out of the way, but just enough to make this possible.

1) Remove spark plug wires (taking note of their original orientation or firing order).

2) Remove coil pack and this connector coming up from the wiring harness (four bolts) (also take note of the two ground wires connected to the front two bolts)

3) With the spark plug wires off, and coil pack removed, you can see a black molded wiring harness secured by two nuts. Remove these two nuts, and wiggle the wiring harness out of the way. (This harness will not move too far, but enough to maneuver your hands in there).

4) From here you can see the 02 sensor below the harness. Unplug the connector for the 02 at the top of the harness. You can also unclip the O2 sensor mating end from the harness by pressing down on the locking clip just under the connector.

5) Place O2 Socket over O2 sensor then wiggle harness towards firewall

6) Using the 22mm wrench loosen and remove the 02 sensor and replace. (Similar to the pictures below). Since the harness is now closer to the firewall, you can insert the wrench between the harness and the engine.

7) After tightening sensor and connecting to the wiring harness; place the harness back to original position and tighten nuts. (Just a suggestion while having the coil pack removed, itâ�?��?�s not a bad idea to clean the coil pack and plug wires before putting everything back toghter).

8)Clear Codes/Reset PCM by removing Fuses 4 and 11 for 10 minutes.

Some CEL codes that may give you the impression that this particular sensor needs to be replaced:
P0133-â�?��?Heated upstream 02 sensor circuit slow response (bank 1)â�?�
P0171-â�?��?â�?�System too Leanâ�?� (bank 1)
P0172-â�?�System to Richâ�?� (bank 1)
P1131-â�?��?Lack of upstream heated oxygen sensor switch-Sensor indicates Lean (bank 1)â�?�
P1132-â�?��?Lack of upstream heated oxygen sensor switch- Sensor indicates Rich (bank 1)â�?�
**Would like to thank â�?��?Williamâ�?� and â�?��?annakobyâ�?� for past threads that made some of this information possible, written by â�?��?mycainsbrokenâ�?�**

**Pictures and Updates by Crystian C. (Golden Tour) 8/11/05**

Thank you Crystian.

That is the best "How To" yet for anything. Honestly. Now if my O2 has a [censored] break, I'll be thanking you.

There is only one thing wrong with the pictures.

Why are you teasing us with a slight glimpse of a Corvair Monza Spyder? Where is the picture of the whole car?

I haven't seen one of those things in years.

That is where high performance "turbo" mufflers came from. It was also the first "high performance" hydraulic lifter cam. There is some automotive history there. Anybody remember "Unsafe At Any Speed"?

ahh, the spyder, i would be ashamed to show the pics. though the car is in great shape, paint, paint, interior, no oil leaks, steering a little bit of play. and the cams tend to stick for a little while after sitting for a month, but they loosen up as soon as the engine temp comes up.

it needs to get a good cleaning before i post pics of it. and yeah its a 63 turbo-charged 4 spd

we also have a 63 falcon with a 170 3spd on the tree.

ill try to post when i clean and wash both.

i was wondering if anyone would notice it.

and i have several words for Ralph Nader!!

Originally posted by Big Jim:
There is some automotive history there. Anybody remember "Unsafe At Any Speed"?

Yes, I do and also learned it in college Philosophy: Ethics in Engineering. Ralph Nader (or was he the exploding Pinto gas tank). Oops, showing my age here.

Edit: Yes, it is (by previous post).

A bit overkill, but what ever works for you. Good write up

yeah i know its a bit of overkill, but some of us need it. Its such a PITA if you cant figure it out. When i first tried it, i tried from the bottom for about 2.5 hours. i gave up and drove around asking different shops. they tried to steal from me anywhere from 80 to 120 dollars because they said it required special tools and it would be very, very difficult. ohh and some said that there would be an extra charge to reset the computer. i couldnt see myself paying 50 bucks let alone 80-120. so i went home.

i had tried crows feet, and since they didnt work for this application, i took them back and while i was browsing, Bamn, O2 sensor removal socket, 10 bucks. and the rest is history.

Wish I had come across this last week. I just changed that O2. Went over the top from the passenger side with big hands/arms & without removing the coil pack. MFin' PITA!

Thanks for the pix. They will be a great help when I change mine in a couple weeks. Definitely not overkill as a picture is worth a thousand words. Great how to made even better with the pictures.

I heart you...

I've got to do this same thing on mondayish and this is definately gonna make it easier, thanks!

yeah me too, stupid o2's, got to replace them .

replacing all of my 02 sensors was a SOB in the worst way. Good luck to u guys......PS: it helps if you have small fingers.

yeah this how to makes it look easy, another required tool would be a midget w/ very small hands, such a pita, I also had to take off my motor mounts to get my hand down there and jack the motor up, but good luck to anyone who tries

Funny, when I did mine 2 weekends ago, I was able to get the O2 socket on the rear upstream and get it off by just taking the coil pack off....and I have fairly big hands. It was a PITA, but not as bad as I thought. The hardest part was getting it tight enough.

Just finished mine. I couldn't even get the O2 sensor socket in there. I tried switching to a crow's foot wrench. no luck there either. I finally got the sensor loose after a couple of hours.

Then, inspiration struck: I have a neighbour who works on cars. He is Vietnamese. His hands are small. 30 minutes later, I am firing up the car!

Ugh, I gotta do this soon. Ive been putting it off since I can clear the light with the Xcal, but enough is enough. Gotta sack up.

Finally changed out my 02 yesterday. This is a great method for doing so, but I must say one thing: You must have some real tiny hands to fit past that wiring harness!!! I could barely get my hand half way past it (while really pushing it out of the way). Painful, but you gotta do what you gotta do. Got my hand far enough in to hand tighten the O2, which was a huge help. If you cant get your hand on it, it would take a while.

Total time: 1 hour. Not too bad at all.

I used the o2 sensor socket to remove the old sensor using the above method. One note on that, my socket had a 1" fitting not 7/8". Also, If you use a bosch replacement part, your o2 sensor socket probably won't work for the reinstall.

Because the bosch's "stem" is much thicker than the motorcraft's, you can't angle the socket on as much. The socket is just too long, the brake lines get in the way. I had to slip a regular 7/8" wrench horizontally on the sensor, mate it vertically with the open end of a long wrench, and tap on the top of the long wrench. Kinda rigged, but it worked. No clue how I'm going to get it off if it fails again.

So to sum it up, ymmv depending on your socket. Better idea is just to buy the motorcraft part in advance.