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RESOLVED: O2 monitor and o2 heater incomplete

39K views 34 replies 15 participants last post by  sanchopwnza 
#1 ·
Trying to get my 2013 GT inspected in NY. I can't get the o2 monitor and o2 heater to ready status. Everything else is ready. I've done the drive cycle thing more than I'd like. It all started last fall. The inspection place said it failed because 2 monitors weren't ready. I normally take the battery out during the winter and store the car. I put less than 300 miles last year due to crappy weather and driving a 2 year old around. Put it away last year knowing it needed those monitors set figuring it was just matter of resetting the pcm and driving it.

I've now put 400 miles on it in 2 weeks and also reloaded the stock tune from the Ford racing one, which shouldn't turn off anything and I've had it on since I bought the car new. Also performed a pcm capacitance reset as well. That's where you disconnect the battery and jump the two terminals together for 30min or so. Live data shows the o2 sensors are working just fine. Long term fuel trim looks a little lean to me but that could be normal. Car runs great.

Any suggestions? I'm reluctant to use the dealer. They don't know much and will just start throwing parts at it on my dime.
 
#2 ·
My battery died this winter due to not starting or driving my 2013. I had to purchase a battery minder/charger and when it reconditioned the battery my BlueDriver was saying that the O2 sensor and O2 heater were no up to reporting as good. It took several cycles of starting, driving and turning off to get it to pass the SMOG ready on the BlueDriver. Driving mileage is not the key, it is start stop cycles.
 
#3 ·
I'd have to guess that you're talking about your O2 sensors. Some of them have a heater circuit in them that helps bring them up to operating temperature quicker. You have 4 and should get a diagnostic code for the correct bank (right or left) and upstream/downstream (before or after the cat converter). Replacing the defective ones might, I repeat might, get you to pass smog (unless the rich/lean mixture that caused the sensor failure is bad enough to kill new sensors).
 
#4 ·
Sorry. I thought it was pretty obvious o2 monitors were correlated to o2 sensors and fuel trim. The sensors are fine. Live data shows them operating correctly. Catylist monitor is ready which won't turn on without the o2(s) working right. I guess more drive cycles are in order. I hate NY.

Only 11k Miles on the car.
 
#5 ·
Gotta love NY! Had the same issue last winter after disconnecting the battery. Went a month and a half past inspection b/c the O2 wouldn’t reset. I have a 3” catback and one thing I heard from several sources was the sensor has to reach a certain temp in order to start monitoring. With a free flowing exhaust (or possibly if you’re driving easy) they don’t get up to temp. Once I thought of this, I drove the car like a 16yr old would. Rev it out, keep it at higher rpms if you can, downshift, get on it, anything to get her hot. A couple trips to/from work (120 miles) and they were set! I even drove around with the drive sequence from Ford on my front seat to show any officers when they asked why I was driving up to 40, coast to 20, up to 50 coast to 30 or whatever the hell it was. Ridiculous for sure! If you haven’t yet, give it a try. Good luck!
 
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#6 ·
Ah ha! This makes sense! I put on borla over axle pipes 2 years ago. My exhaust is a 3" JBA h-pipe, the borla over axle pipes and gt500s. I was told to drive it easy. I will beat it like it owes me money. That's fun anyway. It would be easier if the ambient temperature was > 80.
 
#7 ·
hmmm, yeah you might be onto something with the temperature thing . . . if you were only driving for a short time before the test, they might not have gotten up to temperature . . . try a nice long drive, like at least 30 minutes, before the test; and I guess some heavy throttle / high RPM wouldn't hurt
 
#8 ·
Driven a couple drive cycles with cat temperature @ 1200+ in 5th gear. 6th gear the cats don't go above 900F. Still show incomplete. Going to try getting them hot and driving the hego cycle in normal drive mode (6th) and not sport (5th). No a/c, no cruise control.

This is ridiculous.
 
#9 ·
. . . . This is ridiculous.
yeah . . . I find it hard to believe that slightly larger pipes and freer-flowing muffler could make such a big difference to the temps . . . but just so you don't get all tangled up in "illegal aftermarket exhaust modifications" BS, you might need to put the original exhaust back on, and then try it.

If problem is still there, then you can take it to dealer, I'm pretty sure the warranty on emissions-related stuff is practically forever
 
#11 ·
jth877,

Keep me posted on how you are making out on this. I am going through the same exact scenario with my car. I keep mine on a battery tender all winter and being eight years old this year I replaced the battery in April and the car hasn't been driven much at due to the crappy weather. Tried getting it inspected and failed due to the O2 and Heated O2 monitors not ready and totally didn't think about it i would have waited to replace to battery! I drove the car 400 miles with no luck in having them cycle and did a PCM reset a week ago and nearly 200 more miles nothing.... I am beyond frustrated the car runs perfect has 19,000 miles, no codes, everything is working as it should. It's about to go to the dealership as I am at a loss with it. Only mod on it is the Borla Atak exhaust and Borla said that wouldn't affect the monitors from running and they recommended me resetting the PCM again so here we are. I just can't imagine the free flowing exhaust has anything to do with it but I can't think of anything else the car has never been tuned and completely original other than the Borla mid-pipes and mufflers.

Good Luck and let me know if you get anywhere. I'm ready to really drive the **** out of it to see if that works. Another reason to leave this godforsaken state!

Tim
 
#12 ·
Just to give everyone an update on my situation. I reset the PCM drove over 500 miles and still no O2 or heated O2 monitor cycled. Out of pure frustration I took off the Borla Cat back system, which included the X-Pipe, Mid-Pipes and Atak mufflers and reinstalled the complete factory exhaust. Took the car on ta 30 minute drive and both monitors ran and now I can get the vehicle inspected! Certainly the high flowing exhaust was causing the monitors not to run for whatever reason it was I have no idea. Can an aftermarket tune fix this issue? I still have to get the airbag recall done so I don't be reinstalling the Borla exhaust back on until that is done and all OBDII monitors have cycled.
 
#13 ·
. . . .. I reset the PCM drove over 500 miles and still no O2 or heated O2 monitor cycled. . . . Borla Cat back system, which included the X-Pipe, Mid-Pipes and Atak mufflers and reinstalled the complete factory exhaust. . . . .
thanks for the update, that does seem to defy all logic and mechanical common sense . . .

Just checking -- the Borla "cat back" system is from the catalytic converters back, meaning the factory cats and O2 sensors were in place the whole time? Or does that system remove the catalytic converters and replace them with "off-road" mid-pipe and/or X-pipe?

I doubt it can be corrected with a tune, more often the tunes ARE the problem because they turn off the rear O2 sensors. It might be worth an e-mail to a tuner to explain the issue and ask them (Lito -- support@tudyno.com)
 
#14 ·
Just to give an update. I decided last year with so much going on in my life I just shelved the car for the rest of the summer. Now I'm getting ready to tackle the O2 monitor issue this season. Reading the previous post I will take off my Borla over axle pipes, and maybe the JBA H-pipe- although it did pass with it installed before. Looks like I'll be jacking the back end of the car up 3ft to get the one piece over axle pipes off. That's nerve racking.

The question is whether a custom dyno tune will eliminate this O2 monitor nonsense. Thought?
 
#15 ·
Just to give an update. I decided last year with so much going on in my life I just shelved the car for the rest of the summer. Now I'm getting ready to tackle the O2 monitor issue this season. Reading the previous post I will take off my Borla over axle pipes, and maybe the JBA H-pipe- although it did pass with it installed before. Looks like I'll be jacking the back end of the car up 3ft to get the one piece over axle pipes off. That's nerve racking.

The question is whether a custom dyno tune will eliminate this O2 monitor nonsense. Thought?
I have a 2012 Mustang GT and had returned everything back to stock, for the purposes of smog, except the Borla cat back exhaust. After driving almost 1,100 miles and replacing rear o2’s in desperation, it still wouldn’t clear. I read some of the comments about reinstalling stock exhaust to clear the o2 and o2 heater sensor monitors. I am the third owner of the car and did not have the luxury of reinstalling the stock exhaust. So I tried driving it hard at higher RPMs to get the monitors to clear and was unsuccessful. At this point based upon the previous comments, I came to believe the problem is that the catalytic converters are not getting hot enough at low enough rpm’s for the monitor self test to start. After monitoring the temperatures with a scanner I decided that I needed to create more back pressure. At that point I took it to an exhaust shop and had him install a plate with a hole in it, in each pipe. After about 75 miles of driving in 2 separate drive cycle attempts, the monitors cleared. From that point I easily passed smog, had the restrictor plates removed and everything’s fine. Hopefully this helps someone that is dealing with this problem.
 
#19 ·
777069

This is what I had done at an exhaust shop in each bank. It’s just a piece of metal from exhaust pipe, cut and shaped, then tack welded into place. These plates were put in behind the cat conv. and rear o2.
It’s worth mentioning I have the car back to stock with a stock tune to get this done.
I certainly don’t know all the answers but this is what worked for me.
Now I can put the fun stuff back on and go to the track.
 
#20 ·
Update. Nothing new. I put the stock exhaust back on. Over axle pipes and mufflers. Been driving 2-3 times a week for the last month and O2 monitors still show not ready. Everything is ready. Frustrating.

I hate to use the dealer but that's where it's probably going.
 
#30 ·
Update. Nothing new. I put the stock exhaust back on. Over axle pipes and mufflers. Been driving 2-3 times a week for the last month and O2 monitors still show not ready. Everything is ready. Frustrating.

I hate to use the dealer but that's where it's probably going.
I didn’t see where you said you checked the fuse for the heater circuit….. might want to check it before going to dealer
 
#21 ·
I finally have my car ready for test! It only took 3.5 years. Over the winter I reinstalled the oem h-pipe. Drove it about 100 miles on 4 separate occasions within the last 2 weeks and the o2 sensors now show ready on torque. Must be very sensitive to exhaust mods around the o2s.
 
#22 ·
#23 ·
Hey. I'm also in NY and I've had the same problem for the past few years too. Mine is also a 13GT Auto with GT500AB but I have stock pipes. Also started when my battery went dead with a tune. Flashing the stock tune was no help - neither was changing the downstream o2 sensors. Think maybe the GT500AB are part of the problem? I'm thinking about covering 1 exhaust tip on each muffler with tin foil and a metal hose clamp to heat up the cats a bit more.
So my problem, as far as I can tell, was a small exhaust leak in one of the JBA H-pipe connections. I also had the battery out all winter before I reinstalled it this spring. The o2 monitor and heater would never go ready. Everything else did. Even the catalyst.

I have since put the GT500AB back on and put the ford racing tune back on. It still went ready after a few drive cycles. I have NOT put the borla over axle pipes back on. It's a PIA without a lift and I was thinking of selling the car anyway.

I think the software for the 2013 autos is just really sensitive to leaks. I would get new clamps for the over axle pipes to the h-pipe and new ones for the h-pipe to cats. If you are able, check for leaks. I think they sell smoke machines for that.
 
#24 ·
Your experience similarly mirrors mine. 2013, auto, 9k miles and NY (Moderated) state.. No amount of drive cycles worked.

I had GT500s and an H-pipe for 5 years without issue. I had borla OA pipes for the last 2 of those 5 years. My inspection was normally done right before I put the car away for winter. I then pulled the battery.

The O2 heater and O2 monitor "not ready" problem started on my annual October inspection 4 years ago. For 3 years after that I ran the cats up to 1300F multiple times in every exhaust combo EXCEPT I did not put the oem H-pipe back in. Once I put that back on it was magical. The car went ready after 3 drives totalling about 30 miles. The only mods being the GT500 AB. I then reinstalled the ford racing tune and the car went ready in about the same amount of driving.

I will also note the car ran like (Moderated) when those monitors were not ready. I often could detect a faint odor of gasoline.

I hope this thread helps someone in the future. I too was told by a dealer the absolute wrong thing and had to pay for the diagnostic. Almost everyone said it can't be the exhaust. Well it was.
 
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#25 ·
My GT500s are single tip. I doubt they changed the cat temp much. I ran the cats up to 1300+ for about 5min in a low gear trying to do the 40mph for at least 4min drive cycle thing. It didn't work.

I think the specific auto trans software for 2013 and 2014 GTs is just really picky about the threshold of the cat Temps eventhough you would think the manual trans would be identical. I didn't check my temps as it went ready. I probably should see what they are running at now.

I was ready to put a restrictor in the exhaust as a next try.
 
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#26 ·
Hi Marc,
Your thorough and detailed run down is very much appreciated. I live in NY and have a 2014 5.0 GT Premium with BBK shorty headers, H-pipe, Roush mufflers, AIRaid CAI and original cats. Passed emissions inspection in Sept 2020 with all of these mods in place, including the reduction sleeve in the intake tube of the CAI. Installed a BAMA 87 Octane Street Performance Tune in early January of this year and had to remove the reduction sleeve in the CAI to run optimally. Went to get Inspection done in early October at Ford with that tune in place (and no reduction sleeve), and the O2 & heated O2 monitors were "Not Ready". NO DTC codes observed on my OBD reader Called BAMA about this and they created a new "emission" tune, which I then installed and then drove 106 miles (Bama stated at least 50 to 70). Brought back to Ford, but O2 & Heated O2 monitors still not ready. Drove an additional 203 miles & went back to Ford. Still both O2 monitors were not ready. No codes thrown Reinstalled the factory stock tune and the reduction sleeve & drove 164 miles & went back to Ford. STILL not ready. Still no DTC codes. Talked to Bama & was advised to run through drive cycles Researched drive cycle info and found 2 different ones.
One stated to do the following:

" Accelerate slowly to 40 mph while staying below 2300 rpm. Maintain constant pressure on gas pedal for steady speed of 40 mph for at least 4 minutes, up to 5 minutes, preferably for at least 4 miles. No stopping and do not let off gas pedal."

That didn't help.

The second one stated the following:
" Pre-Conditioning Requirements: Fuel level between 15% and 85%. All accessories off
Start the vehicle and idle for 4 minutes.
Idle the vehicle in Drive for 1 minute.
Accelerate smoothly with a steady foot to 45 mph. Stay in second gear for 5 seconds during this acceleration. Get to 5th gear.
Maintain a 45 mph speed for 30 seconds
Stop the vehicle.
Idle the vehicle in Drive for 1 minute.
Accelerate slowly and smoothly and drive for 15 minutes at speeds between 15-35 mph. Within this time, stop at least 5 times with ten seconds of idle time, and have at least 3 periods of steady speed for 90 second durations. Use slow throttle accelerations.
(Note: During this section I drove at speeds of 15 and 20 mph for at least 90 seconds at each, and then at 25mph for about 3 minutes, followed by 30 mph & 35 mph for at least 4 minutes or more at each one)
Drive the vehicle between 45-60 mph for 8 minutes.
Then, maintain a steady speed between 45-60mph for 5 minutes.
Followed by driving the vehicle at any (varying) speed(s) between 45-60mph for 8 minutes.
Stop the vehicle and idle for 40 seconds."

That still didn't work.

Drove another 550 miles of normal driving (both highway and around town), but still not ready.

Went and bought an OBDLink Mx+ reader which reads both sides of the ECU.
Connected and obtained a U0401-81 DTC (Invalid Data received from the ECU/PCM)

Stock tune still in place.
Called BAMA & gave then the rundown.
They stated to do a "hard reset" by disconnecting the battery for at least 30 minutes. And to check to ensure there was no corrosion or oxidation on the battery terminals and battery lead connectors, as well as the Ground connection on the alternator, which I did. They also stated to drive for at least 70 to 100 miles & check readiness again. The Ground connection on the alternator was covered by a rubber cup and was absolutely clean with no corrosion whatsoever. Also no corrosion on battery terminals or battery connectors either, but still used a steel wool and wire brush to give everything a good cleaning to get shiny metal contact for best possible connection. Drove 140 miles but O2 monitors still not ready.

I am at my whit's end.
Should I consider cleaning the MAF sensor with MAF cleaner?
I will have to see how hot the CATs actually get by trying out what you suggest, but was wondering whether or not it would be wise, or OK, to temporarily either place perforated foil on the muffler tips or to temporarily stuff the tailpipes with steel wool to reduce the throughput of exhaust flow with the intent to increase back pressure and to try to get the CAT temps higher?

Any helpful info from anyone regarding this would certainly be appreciated .

Thanks very much in advance.
 
#27 ·
I have a 2012 GT500 with Cat, O2, and O2H not ready. Changed out the battery a few months ago when the problem started. Only mods are reusable air filter and ford racing mufflers. I put the stock mufflers back on today— tomorrow I’ll be driving around some more. Wish me luck.
 
#28 ·
I was able to get the Cat monitor ready, but not the O2 or O2H monitors. Everything is stock—filter, intake, exhaust, tune. Monitoring the cat temps, it’s easy to keep them over 1350, but tougher to keep them under 1100 after the hot cycle is done. So today I drove the cold cycle (35-40 mph, 5th gear), w/o the hot cycle first, since the cat monitor was already good. It definitely stayed under 1100 for 10 min. Then as a backup I did the hot run followed by the cold run, as best as I could. O2’s still not ready.
 
#35 ·
I had the same problem with my 2019 ecoboost: O2, O2 heater, and cat monitor showed incomplete for months. The only mod installed is an upgraded intercooler. I tried everything I could think of and just about everything I could find suggested on the internet.

Out of desperation I took it to the dealer who found two issues that weren't throwing codes: a fuel pressure sensor and an exhaust timing issue. Replacing the sensor didn't help, and some digging found that the cam gear that drives the exhaust cam was stuck with the timing advanced 4 degrees (apparently, 5 degrees is necessary for the PCM to throw a code for this). Replacing this (and the camshaft itself since we were already disassembling to this point) fixed the issue. The sensors all initialized after about 200 miles of driving.

Just thought I'd share since I've seen quite a few threads about this issue and not so many happy endings.
 
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