Rear O2 sensors?

[MOTANGT]

Happy New Year to everyone. Been out of the loop for a while while trying to find the vibrations in my car. What I ended up doing is installing the adj prothane motor mounts and almost all of my engine, tranny and shifter movement dissapeared. Anyway next Month I'm due for my first computer rape for emissions and my car is still reading faults for rear O2's and will not stay cleared. A couple of Months back I made an appointment with Marty @ Extreme Performance and got my Dyno tune "finally" and we messed with the settings for the O2,s but no luck. So far I've checked the connections, made some anti fouler O2 extensions and threw a fresh set of plugs in and cleared the codes. On the way to work this morning the codes popped back up???? I don't know what else to try other than replacing both sensors or am I missing something? I've read many posts that guys are passing using the O2 extensions on straight pipes with no cats. Do I need to double stack the extensions? Sorry if this belongs in the tuning section.

[PapaVolume]

Have you tried getting some MIL eliminators to put in the rear o2 sensor harness?

[MOTANGT]

No not yet. Do they need to be made from scratch? I've read that they are hard to find now days to purchase. If they do need to be made can I use the O2 cable extenders as my link?

[Wharf Rat]

I'm not positive but I think the MIL eliminators don't work on the 05+ Stangs. I had longtubes on my 06 and 07 and had the O2s turned off in the tune. No check engine light but I have no idea if there would have been codes (I assume there would have been).

[PapaVolume]

You know, thats a good point. I havent come across this issue with any 05+ cars since I always just suggest turning them off in a tune so I havent tried MIL eliminators on them. I had ran them on my personal 98 almost 10 years ago before it was tuned and it worked well. I dont understand how there is a check engine light on for those if it was turned off in the tune.

[MOTANGT]

All new canned tunes have to have the O2's turned back on I'm guessing that the EPA found out that companies were turning off parts of the emission systems on newer cars. The O2's turned off in the tune causes a readiness failure at the emission station so you fail until you turn on the rear O2's and find a way to fool the computer. Some people are using the eliminators or double stacking spark plug antifoulers. Most people are having luck changing the voltage, temp and return rate times modified in there tunes but unfortunately I've tried all but the MIL eliminators and or replacing the sensors all together. There are hundreds of 05+ mustangs that have passed the OBD2 test with more modifications that I have but there is no difinative answer. I really wish there was.

[Blackmagic1]

Mine failed at emissions. Showed"Open Loop Fail". Which the rear 02's were turned off. Had Keith at AZ Dyno Chip download a program in my SCT tuner. Downloaded into car, went to emissions.....Pass. Then flashed back to tune i was running.

[MOTANGT]

Checked my codes when I got home and found that bank1 is no longer active but bank2 is still not happy. I think I'll order a set of replacement O2's over the weekend and see if this resolves the issue. That would sure be nice if it was that easy. Is there an option in the SCT to datalog the voltage and temp for the rear O2's?

[Blackmagic1]

I've never checked on mine if it can. I have the SCT2 tuner, now SCT3 is out. You might check SCT website to see if it can.

[MOTANGT]

Well I failed emissions. Got an email going to Marty to find what else I can do. P0430 popped up one mile before I got to the station :censored:. So far the car has been tuned with the cats and o2's turned on and have replaced rear o2's. Fresh plugs and about 350 miles put on the car since. I'm also running the anti fouler o2 extensions and the only thing that is left is swapping the driver to passenger side cables. The only reason that this might be an option is that a local shop had my transmission out of my car seven times for the clutch and might have crossed the connectors during installation. What do you think?