i would just take the chance and use it... is it under warrenty? if not i would keep askin round, or if you have a volvo mechanic in your area he would deff be able to help you out

 

Dammit..... ground of that little tab of plastic and the sockets fit perfectly after that. I drove it for maybe 5 miles since and it immediately threw codes 2-3-2 and 1-1-3.

going by this chart....
Engine and OBD Diagnostic Codes

113 means Fuel trim (lambda control) too lean or rich Cause: Mixture incorrect; O2S wiring fault

232 means Fuel trim (lambda control) too lean or too rich at idle }If too rich: high fuel press., leaking injector

Argh... this car is impossible.

 

Dammit..... ground of that little tab of plastic and the sockets fit perfectly after that. I drove it for maybe 5 miles since and it immediately threw codes 2-3-2 and 1-1-3.

going by this chart....
Engine and OBD Diagnostic Codes

113 means Fuel trim (lambda control) too lean or rich Cause: Mixture incorrect; O2S wiring fault

232 means Fuel trim (lambda control) too lean or too rich at idle }If too rich: high fuel press., leaking injector

Argh... this car is impossible.

EDIT: Also, this morning when i first turned it on, the idle was all over the place, dropping down to 500-400 at times and then up to 1k rpm. When after it warmed up the rough idle would jump around maybe 100 rpm. When it was cold and I would accelerate, it would pause for a moment, the idle would drop off completely, then it would catch and lurch forward. Its terrifying in traffic when you have to get moving. Now that it is warm it doesn't seem to do the lurch thing. It just idles rough. I will check mileage later today. Hopefully I have a chance to reset the computer by pulling the battery before I do. I did reset the codes so that it reads 111 now.

 

So it looks like 113 was the 1st code. It sounds like the O2 sensor is bad. By the way you should not have to "splice" in the O2 sensor wire. It comes with the right length wire and connector.

 

To be more clear, this is the history of my oxygen sensors.

1. The original sensor did not throw codes, but I was getting 17 mpg freeway with it.

2. I bought a 2nd sensor. This sensor was generic and needed to be spliced into using the original sensor wiring. it only cost around 20$. I did a 1500 mile trip with it getting 21 mpg. I started getting codes and then I had trouble with the idle air control valve which lead me to flooding the engine many times and covered the sensor in carbon. I cleaned the sensor by burning the carbon off with a torch, but it kept throwing codes so I bought a 3rd sensor.

3. The third sensor(60$) I got had all the wires and the socket attached. I wasn't supposed to have to modify it. It was listed for cars without EGR(exhaust gas re-circulation) The socket didn't fit the one in my car. I modified the socket to fit by sanding a little piece of plastic off of it. Someone above claimed that the sensor itself was the same but the sockets were different. Other places say that oxygen sensors in general will be the same and some places say they are different. I have found nothing about these specific cars. This sensor throws codes and I just took a 160 mile trip and I only got 13 mpg on a freeway.


---->>>I need to know if these sensors are really all the same and its something I did with the wiring or if it is randomly bad. If the sensors are different for cars with EGR, I will need to know if my car does have EGR and if I should get a 4th sensor(91$). The sensors I have bought so far have all come from RockAuto Auto Parts

 

Bought a 4th sensor. This one is OEM Bosch. Correct connector and such. Installed it in and no codes so far for 600-800 miles. Still am getting 16-17 mpg highways.

New developments.... Went to a monro garage and got an oil change because I'm at college and don't want to make a mess in my landlords driveway. Drove it about 100 miles afterwards and a weird popping/clicking noise developed. When I checked the oil it was way too high. Had no time to fix things cause of school and such. Maybe drove it 100 miles more hoping it was the exhaust gasket.

I drained the extra oil(when landlord was gone at night in case I made a mess) and tried finding the source of the sound with a plastic hose to my ear. It seems to be coming from the crack between the block and the exhaust pipe coming from the #1 cylinder on the side closest to the spark plug. I'm about 80% positive that that is the source of the sound. I will check thoroughly when it is warmer and less wind and daylight. Hopefully it isn't something really bad.

And something that made me happy..... In my quest to find the source of that new sound, I found a gigantic hole in the pipe leading from the air mass meter to the turbo. Its round and almost the size of a dime. It looks almost like someone took a screwdriver and punched through it. This could be the source of my bad mileage.

I just got a full tank of gas and im going to tape up the hole and see if my fuel economy improves. I'm currently looking for a source of a replacement rubber pipe. There is a junkyard between school and home (75 miles from here) so if I head home next weekend, I'll see if they have any old Volvos with hole-less hoses if I can't find something online.

Will continue to update.....