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Catalytic Converters

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Charlotte, NC, USA
#1
Catalytic converter #3. First 2 replaced due to crack at the weld, passenger and driver side. This one is driver side. This is NOT at a weld, but a fractured pipe. Closest weld is at the very top where a support hanger rod is welded to the top of the cat pipe. 45 years of driving vehicles with CCs and I've replaced more cats in 8 months than the previous 45 years. Good news all covered under warranty, and available. China balloon mystery solved.....pallet of CCs to FOMOCO express delivery
 

Cdubya

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#3
Is yours a MY2020? When you had them replaced, did you get one the new version with the cast flange?
 

OP
M
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Thread Starter #4
Is yours a MY2020? When you had them replaced, did you get one the new version with the cast flange?
Yes 2020. Not sure of the cast flange. Assuming you mean where it bolts at the engine. I’ll look this weekend. I’m putting muffler tape on it so it doesn’t sound like a 60k POS beater until I can get it in to replace.
 

LondonST

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Location
london, ontario
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2020 Ford Explorer ST
#5
just had mine replaced yesterday under warranty as well. boy do they stink when breaking them in. bonus that they also did the blue screen back up camera fix as well.
 

zdubyadubya

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Utah
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2020 ST
#6
jeez. at this point I would just be walking into the dealership with a set of aftermarket catted downpipes and tell the service advisor "here put these on and hang onto the FoMoCo supplied ones for a rainy day".
 

OP
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Thread Starter #7
Is yours a MY2020? When you had them replaced, did you get one the new version with the cast flange?[/QUOte
Is yours a MY2020? When you had them replaced, did you get one the new version with the cast flange?
Appears I did. While I can't get a clear view from under the car or up top, I checked the invoice and it listed M1MZ-5E212-A and M1MZ-5S213-R. Both listed as Converter assembly. Said it replaces L1MZ series . Best I can tell the new series has the cast in flange. Pictures I can find show a much more robust design.
 

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Location
Honolulu, HI, USA
#8
Mine also, 2020 ST. Part of recall about exhaust smoke in the cabin on hard accceleeration. Done twice over six months and finally okay.
 

Skeek

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Oregon
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2020 Ford Explorer ST
#9
Catalytic converter #3. First 2 replaced due to crack at the weld, passenger and driver side. This one is driver side. This is NOT at a weld, but a fractured pipe. Closest weld is at the very top where a support hanger rod is welded to the top of the cat pipe. 45 years of driving vehicles with CCs and I've replaced more cats in 8 months than the previous 45 years. Good news all covered under warranty, and available. China balloon mystery solved.....pallet of CCs to FOMOCO express delivery
New here and curious what prompted you to identify this issue. Was it a loud noise or smoke from the exhaust? Just picked up a 2020 ST and am wondering if there are any symptoms I should keep an eye out for.
 

Cdubya

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#10
it may be louder, you may smell exhaust in the cabin but you may not. Best way is visual inspection. It's hard to see the welds by the flange. my crack was the weld further down. also the flex sections in the midpipe are prone to rattle then fail. keep an eye on those too.
 

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Location
Honolulu, HI, USA
#12
My 2020 ST had exhaust cataylitic sulphur smell at start. Got worse over time. Under hard acceleration, cabin would fill with exhaust smoke in short time. First repair failed. Second time has worked now for about a year.
 

Skeek

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Oregon
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2020 Ford Explorer ST
#13
My 2020 ST had exhaust cataylitic sulphur smell at start. Got worse over time. Under hard acceleration, cabin would fill with exhaust smoke in short time. First repair failed. Second time has worked now for about a year.
Nothing on cold start for me but I do smell it a bit on HARD acceleration, which I didn't find too unusual at first. No visible smoke that I could notice. Thinking it might pay to have it checked under warranty though if this is a known issue,
 

Cdubya

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#14
You should not have exhaust smells in the cabin, period! If you do, tell your dealer and have them check, preferably when you bring it in for an oil change or other. They shouldn't charge you if you are under warranty.
 

OP
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Charlotte, NC, USA
Thread Starter #15
New here and curious what prompted you to identify this issue. Was it a loud noise or smoke from the exhaust? Just picked up a 2020 ST and am wondering if there are any symptoms I should keep an eye out for.
sounds like a hole in a muffler. Very noticeable when idling. Look for black staining on the pipe. 2020s have a recall on them. Next time on a rack have someone check it out. Cheers
 

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Location
Honolulu, HI, USA
#16
Mine started the same way, small at first, then got worse. Get it fixed.
 

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71
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Location
South Carolina
Vehicle
2022 Explorer ST
#17
Are these signs of failing catalic converters? I plan to get aftermarket exhaust and Downpipes in the future. I have not seen smoke or smelled exhaust fumes. However, only one time I smelled rotten eggs a week or 2 ago.
 

Attachments

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Location
Honolulu, HI, USA
#18
Mine was from bad weld that was quickly fixed at the dealer under a recall notice. I had it done while the car was up for an oil change. It took a second visit to get it done correctly about a year and half ago.
 

Cdubya

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#19
Are these signs of failing catalic converters? I plan to get aftermarket exhaust and Downpipes in the future. I have not seen smoke or smelled exhaust fumes. However, only one time I smelled rotten eggs a week or 2 ago.
that black soot isn't necessarily a problem. BUT when it's coming from a weld, there is definitely a crack there. Bring it in...
 

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Location
Jessup, MD, USA
#20
Mine cracked yesterday while installing a Thermal 3" exhaust. I know it's covered under warranty, but do you think they would turn me away due to the catback?

I have a set of Whoosh DPs, do you think it would be hard to find a dealer that would be willing to throw those on instead?
 



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