96 850 T5 Rear O2 Sensor missing? Topic is solved

[erikv11]

It is a hassle to get it going, but not very expensive if you can come up with an old Windows box/laptop. Then you only need ~14-16 V external power supply (or use the alternator/battery in your car if you can get it to stay stably above 13.5 V), a $15 USB to OBD2 converter, and some wires.

computer
USB/VAGCOM cable (get the right one!)
16 gauge wires and little spade connectors (or better yet, cut the ECU connectors from an old wiring harness!)
time
All software is freely available, http://m44.wikia.com/wiki/M44_Wiki

I found it cheap to cobble it all together (and I am a cheapskate!), but for me there was a learning curve before I was confident with the flashing.

I wouldn't do it just for the rear O2, mine was also a lol post like yours, just tossing it out there. Rear O2 and SAS are market-specific emissions items. Rear O2 can sometimes become a hassle on these aging cars. Etc, etc.

[tryingbe]

Wish i only had 1 sensor. lol

Set yourself up to flash the ECU, you can turn the rear one off with a click of the mouse.

Cost doesn't outweigh the benefit. Unless I'm over thinking of all the items I'd need to make it happen?

Under $30 of parts. I can flash both M4.3 and M4.4 ECU.
http://m43.wikia.com/wiki/M43_Wiki

I'm currently running a M4.3 ECU with blue injectors.

[beigg]

It is a hassle to get it going, but not very expensive if you can come up with an old Windows box/laptop. Then you only need ~14-16 V external power supply (or use the alternator/battery in your car if you can get it to stay stably above 13.5 V), a $15 USB to OBD2 converter, and some wires.

computer
USB/VAGCOM cable (get the right one!)
16 gauge wires and little spade connectors (or better yet, cut the ECU connectors from an old wiring harness!)
time
All software is freely available, http://m44.wikia.com/wiki/M44_Wiki

I found it cheap to cobble it all together (and I am a cheapskate!), but for me there was a learning curve before I was confident with the flashing.

I wouldn't do it just for the rear O2, mine was also a lol post like yours, just tossing it out there. Rear O2 and SAS are market-specific emissions items. Rear O2 can sometimes become a hassle on these aging cars. Etc, etc.

Does it open up ABS, SRS, and trans tuning/editing as well?

[tryingbe]

Does it open up ABS, SRS, and trans tuning/editing as well?

Disable the the lights? Take out the light bulbs.

There is no trans tuning, other than NORMAL and PERF.

[erikv11]

Under $30 of parts. I can flash both M4.3 and M4.4 ECU.
http://m43.wikia.com/wiki/M43_Wiki

I'm currently running a M4.3 ECU with blue injectors.

A question for you: why run 4.3 when you could drop a 4.4 ECU into your 850? Just because you had the 4.3 hardware available to you but not the 4.4?

[beigg]

Even though it's a modern system over the .3, wouldn't going .4 be a derogate when the intent is enhance the performance null emissions.

[tryingbe]

Under $30 of parts. I can flash both M4.3 and M4.4 ECU.
http://m43.wikia.com/wiki/M43_Wiki

I'm currently running a M4.3 ECU with blue injectors.

A question for you: why run 4.3 when you could drop a 4.4 ECU into your 850? Just because you had the 4.3 hardware available to you but not the 4.4?

Several reasons. I have a manual swapped 850 turbo, and I tried the manual bin file offered on the m4.4 wiki website

1. Manual M4.4 tends to hold the RPM for around half a seconds while I am shifting.

2. The off the shelf manual M4.4 calibration fuel table is very lean (13-15) above 5psi.

3. The manual M4.4 calibration idle is really lean 16-17 a/f whiles ilding when you first plug it in. It gets better after 10-15 mins of driving, but every time you unplug the ECU, it does the same thing again.

4. The manual m4.4 calibration fuel injector scale for the MPG gauge is off by 23%.

While I can change the calibration for number 2-4, there is nothing I can do for number 1. I used M4.4 for a 5500 miles road trip thinking I'll get used to the RPM holding, nope, it just made me hates it more.

So, I use the modified version of M4.3 627 bin file that does what I want.
https://www.matthewsvolvosite.com/forums ... hp?t=76990

[tryingbe]

Venderbroecks made an add-on hardward just so the M4.4 ECU will drop the RPM faster.
http://volvospeed.com/vs_forum/topic/16 ... nt-2364101

[erikv11]

OK I remember that discussion now about the RPM hold/drop, thanks. I was wondering if I was missing something I might want to consider for my own 850, but I guess since it is an automatic I am not. Oh well.