Cannot pass emissions
Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
ALWAYS use Motorcraft plugs in a Ford
You are just too rich on the CO is your problem
Could be the injectors you replaced or a catalectic converter that is hollow or has very little substrate left inside
Could be the MAP sensor
Have you checked codes?
Custom exhaust and a high flow cat make little sense if trying to pass I/M in UT
I was an inspector here in UT for 30+ years
Your air pump is there and working?
You are driving a 5.8 with dual thermactors?
Ford put 2 air pumps on some of them and a big honkin cat for a reason
You may need to register it in Box elder County or another one with no I/M with your mods
With no cat, those run about 4-5 percent on the CO
A working cat gets them down to .06 or so
Good luck
You are just too rich on the CO is your problem
Could be the injectors you replaced or a catalectic converter that is hollow or has very little substrate left inside
Could be the MAP sensor
Have you checked codes?
Custom exhaust and a high flow cat make little sense if trying to pass I/M in UT
I was an inspector here in UT for 30+ years
Your air pump is there and working?
You are driving a 5.8 with dual thermactors?
Ford put 2 air pumps on some of them and a big honkin cat for a reason
You may need to register it in Box elder County or another one with no I/M with your mods
With no cat, those run about 4-5 percent on the CO
A working cat gets them down to .06 or so
Good luck
Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
Noted, I will look into some motorcraft plugs. I didn't replace the injectors the PO did. I will look into the MAP sensor. There are no codes, just 111. The air valves didn't work along with the check valves and solenoids, I passed the last couple of years with an improper thermactor system. It only had the one pump in, I replaced it with one from the junkyard due to the last one grenading lol. I took it all out since none of it worked and was taking up room in the engine bay. I will look into some new parts and into hooking it back up. I have thought about registering it in a different county, I will look into it. Very interesting so it seems like this cat is working to an extent. Thank you for your help it is very much appreciated.
Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
Also the year before last it passed, but the PO had hollowed out both cats, so I have no idea how it had passed previously.
Anyways I took out the y pipe and cat, and the cat completely melted. I am trying to upload a picture but it isn't cooperating. My guess is when I was dealing with an ignition system failure it caused unburned fuel to enter the cat and melted it. As I dealt with the spark issue last month, and I had looked at the cat previously and it didn't look like that lol. I will look into getting another one, I am looking at one off of summit racing made by magna flow. This is the one I am looking at, https://www.summitracing.com/parts/mpe-94109?rrec=true.
Anyways I took out the y pipe and cat, and the cat completely melted. I am trying to upload a picture but it isn't cooperating. My guess is when I was dealing with an ignition system failure it caused unburned fuel to enter the cat and melted it. As I dealt with the spark issue last month, and I had looked at the cat previously and it didn't look like that lol. I will look into getting another one, I am looking at one off of summit racing made by magna flow. This is the one I am looking at, https://www.summitracing.com/parts/mpe-94109?rrec=true.
Lead Driver
Joined: Sep 2002
Posts: 9,474
Likes: 2,009
From: North Texas
Yikes. Truck will be faster and better econ with fresh one.
10/10 would investigate how it came to fruition.
10/10 would investigate how it came to fruition.
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Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
So I had an intermittent stalling and ignition system failures and I think that during that time the engine was dumping a lot of unburned fuel downstream. The truck would just die and lose spark so I think the injectors were still firing dumping a ton of fuel into the already hot cat.
Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
Yeah it got COOKED, this was over the course of less than a month, so it happened very rapidly.
Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
I was curious about the catalytic converter that I installed last year, mainly I was wondering if it was getting up to temperature to actually do its job. I can't really stick a thermometer in the cat so I measured the outside temp of the cat and it was 70* F after letting it idle for about 10 minutes. Took it for a drive on the interstate and then measured it and it was at 110*F. Outside temperature is around 40*F. I would think that it would be a lot hotter, the long tubes and y pipe were about 350*F but as soon as it hit the cat it drops significantly. This may be a big contributing factor, I will do some more research into the exterior temperature of catalytic converters but ideally I would like to measure the internal temps.
Thread Starter
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Tuned
Joined: Apr 2023
Posts: 468
Likes: 67
From: Near SLC Utah
Lol, yeah its messed up. It will be a lot happier with a new one lol.