Contour Enthusiasts Group Archives Forums General Troubleshooting Code P1131

Well I found the part, but not the part #, sorry. If you dont find it I will be able to get it to you first thing in the morning when I get to work.

The one for the Contour's upstream sensors should be a square plug with 4 male pins on the oxygen sensor side.

The downstream sensors should be a round plug, with 4 male pins on the oxygen sensor side.

Make sure you're not accidentally looking at the downstream sensor connectors.

You want to replace the upstream sensor.

SMP has a catalog at http://www.smpcorp.com -- check the part # there.

I found the Bosch part number, but I think the sensor I have may be right then. It does have 4 male ends, so I'm guessing I was looking at the downstream sensor. I was looking at the one just to the right of the coil pack. So I'm guessing thats not it, right?

If it's the one behind the coil pack then it is the right sensor but you cannot see the connector without removing the coil pack--it is attached to the hard plastic wiring harness "conduit" on the back of the engine.

Ehh, another way to know is that the upstream connectors are BLACK. The downstream ones are white or green, as I recall.

Or check the front of the engine right near the dipstick, you'll see an oxygen sensor connector plugged in there which leads to an oxygen sensor right next to the oil filter.

I'm in the process of changing that O2 sensor right now. What a complete PITA to get out. If that plastic conduit wasn't there, it would be easy. I had to take a break before I took a lump hammer to the whole engine.

Getting it OUT wasn't the problem when I did it. Getting it IN was.

I couldn't get it started from the top, so I had to crawl under the car and get started from the bottom. You know how much room there is to get your hand/arm up in there? Not much. Fortunately, I'm pretty thin. If I were any bigger, forget it. I wouldn't have been able to complete the job.

After I got it tightened from the bottom and tried to put the oxygen sensor socket on it is when I realized that it won't fit over a Bosch sensor.

So I had to go and get a 7/8" wrench from Sears to finish the job.

The plastic conduit can be moved (slightly) out of the way by removing the two bolts holding it down.

I did NOT have to move the plastic conduit when I did this on a '95 V6 Contour but the "vapor management valve" didn't exist on that car and so wasn't in the way. What a dum*** place to put that thing, anyway. There's room further to the left, near the computer, where the ignition module ISN'T on a 96+ car.

Thanks ...

I moved the conduit as best I could when I started the work but unfortunately, I still cant get the sensor out. I have it loose but just cant get it all the way out. I thought I could get it done with a 7/8" crowfoot on a 3/8" ratchet but the arm isn't long enough. My hands are too big to fit down there in the gap either. To give you an idea, I cant even get at the rear clips on the airbox.

So I had to walk to Home Depot and thankfully they had a 7/8" wrench thats a little longer than the ratchet.

Here goes nothing !!