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Issues Passing I/M Inspection

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1
0
Exp. Level
Under 3 Years
Charlotte, NC
I have a 2008 ford 4.6L mustang I bought recently. I got it off auction so I don't know anything about the vehicles mod history.

From what I can tell, the owner put on Borla exhausts, cams, and a tune. The owner left his original SCT XCalibrator 2 tune installer with 2 tunes and 1 stock tune on it.

I need to pass I/M readiness, but my Cat, O2, and O2 heater sensors are incomplete. Ive tried all the drive cycles I can find, and have put on over 150 miles trying to get them to complete.

I wonder if the tune has the rear O2 sensors turned off to keep the MIL from turning on. I'm also wondering if the high flow muffler delete Borla exhaust’s will affect the completion of the sensors.

Ive read in other forums that people go back to stock exhausts and stock tune and have the issue fixed that way. But I don't have the luxury of having the stock exhausts with me. Ive read about other people putting plates in their exhausts to restrict airflow and allow the CAT to heat up to the correct activation temp.

If you guys have any solutions or any ideas, let me know! Ive been trying to fix this issue for the past month, and I need to pass inspection asap in 2 weeks. Any help is greatly appreciated 🙏
 
6,361
8,183
If it still has the cats, try going back to a stock tune, do they do a visual check, or just exhaust sampling?
If not then you'll need some aftermarket cats to get you bye, all NEW ( aftermarket)exhaust come that way thanks to our overlords
 
I am no help, but i struggled with the same thing on my 2012 and changing exhaust was the solution. I went from a really noisy flowmaster to a more reasonable MBRP, so if you can figure some way to add more restriction it would probably do it.

Once I changed my exhaust, the monitors ran in 10 minutes.
DaveW
 
1,161
2,116
Exp. Type
Time Attack
Exp. Level
5-10 Years
SoCal
I have a 2008 ford 4.6L mustang I bought recently. I got it off auction so I don't know anything about the vehicles mod history.

From what I can tell, the owner put on Borla exhausts, cams, and a tune. The owner left his original SCT XCalibrator 2 tune installer with 2 tunes and 1 stock tune on it.

I need to pass I/M readiness, but my Cat, O2, and O2 heater sensors are incomplete. Ive tried all the drive cycles I can find, and have put on over 150 miles trying to get them to complete.

I wonder if the tune has the rear O2 sensors turned off to keep the MIL from turning on. I'm also wondering if the high flow muffler delete Borla exhaust’s will affect the completion of the sensors.

Ive read in other forums that people go back to stock exhausts and stock tune and have the issue fixed that way. But I don't have the luxury of having the stock exhausts with me. Ive read about other people putting plates in their exhausts to restrict airflow and allow the CAT to heat up to the correct activation temp.

If you guys have any solutions or any ideas, let me know! Ive been trying to fix this issue for the past month, and I need to pass inspection asap in 2 weeks. Any help is greatly appreciated 🙏
Make sure your battery is 100% by having it tested. The emission systems on these cars are very sensitive to voltage. I was experiencing the same issue with my 2014 where it wouldn’t complete a drive cycle. It was a weak battery that was keeping the system from seeing a required voltage to start the drive cycle.
 
I second the advice above. Check the battery voltage. Put the exhaust as close to stock as you can. All assuming the tune is not turning off rear O2.
On my 2012, I could not get it to complete the drive cycle for the rear sensors unless I use the stock mid pipe. I only have GT500 axle-back mufflers with an X-pipe retaining the stock cats, which should technically be legal for emissions if the drive cycle would complete.
 

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