Cat delete FOLLOW-up

Following-up on the post a few days ago. My 2018 MAX was complaining about the catalytic and emission sensor systems. Other high-mileage owners have began replacing converters, so I assumed it was my time. Being a little short on funds I thought I’d find a quick (likely temporary) work around by removing the converters and using a tuning program to shut down the system.

First, I shut the rear emission systems down. Took the truck for a drive. No new lights. Ran great. Like really great. Which told me the ecm was pulling performance out. And I had isolated the problem. (I’ll relay the specific codes when I get back on the tuning program.)

Next. Why stop there? Just cut them off. So I straight piped it. Started it. Didn’t sound any different, but I immediately had a new service light about an electrical issue with the emissions. Took it for a drive. No annoying droning. Ran ok… Like maybe it was pulling back again with the CEL.

My solution now is to plug the converter sensors in and secure them because I think it still detects some error in electrical current. I’ll do this and report back in n this post this weekend.

Then I got to looking at the converters. There is absolutely no signs that they are clogged. As well as one can see through them I see clear sharp honeycomb all throughout. People are replacing them at 130k. I’m currently over 140.

With that said, I think I’ll definitely pull the y and reinstall them. Even though there is no droning or sound change really at all, the smell is too much for a garaged vehicle. Wife isn’t happy.

Do what you want with that information! Thanks

Here are my questions?

Why not update the original thread? Moving on.

Did you try replacing the sensors, BEFORE disabling the "Rear Emissions System"? If the Cats look good? Maybe they weren't the issue?

Also, technically a cat can "look" good, but not actually be doing the job. Clogging is not the only way they fail.

They stink unbelievably, Its amazing. My friend had a LT1 with no cats and it stunk so bad that driving with the windows down around town was painful.

Deadman said:

They stink unbelievably, Its amazing. My friend had a LT1 with no cats and it stunk so bad that driving with the windows down around town was painful.

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Yes. I’m around i/o marine engines and old school street cars very regularly as part of my job. I figured any warning about smell was over exaggerated. Wrong! No amount of wishful thinking on my part was going to make that smell go away!

That's funny on the smell, I've noticed that even with the aftermarket performance cats, every now and then I can get a pretty nasty smell. Only really seems to happen after I've really pushed it and then come to stop.

blue_roster_cult said:

Yes. I’m around i/o marine engines and old school street cars very regularly as part of my job. I figured any warning about smell was over exaggerated. Wrong! No amount of wishful thinking on my part was going to make that smell go away!

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Hey, cats and dogs aside.... talk to us more about the reliability of these vehicles at higher miles. Most of people here are reluctant to keep them beyond the warranty, especially the 2018 is getting very bad reputation. Some specific questions:
- Did you replace the cam phasers? are they rattling?
- How is the transmission doing after all these miles? any service done?
- How is the interior holding up? the driver's seat has been reported to collapse at low miles.
- Any other major failures?

In all, I will be super happy if only the cats fail after these miles.

Soliyou said:

Hey, cats and dogs aside.... talk to us more about the reliability of these vehicles at higher miles. Most of people here are reluctant to keep them beyond the warranty, especially the 2018 is getting very bad reputation. Some specific questions:
- Did you replace the cam phasers? are they rattling?
- How is the transmission doing after all these miles? any service done?
- How is the interior holding up? the driver's seat has been reported to collapse at low miles.
- Any other major failures?

In all, I will be super happy if only the cats fail after these miles.

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If everyone can reserve judgment, here are the facts.

I bought this 2WD limited MAX with 70k, I’ve put 70k on it. It was a RENTAL from CA :/

My wife drives it, and apart from the initial excitement of hearing a turbo spool up, these miles have been easy miles. Ive been on two long distant vacations with it.

I’ve changed the oil 7 times using Schaefer’s 5w30 full synthetic, 500s filter.

Changed the plugs around 100k because it was lazy on hills within city limits. The transmission should downshift but seems to refuse. I thought I detected a misfire. Plugs didn’t help with that. That’s not a transmission issue per se. The transmission is terrific thus far.

I’ve done no other routine service work—not even on the transmission.

Shocks leaked out, but I never bothered replacing.

Cam phasers were serviced by Ford before 100k. Once again, they are again making noise at start up.

Had a coolant leak at one of the y tubes going to heater core. I think that was from being poorly secured during cam work. It dripped down on the passenger turbo for some time before I got to repair it.

Sunroof is jacked. Ford fixed it and it is still jacked.

Interior is great. I have 6 kids and they do their part to try to destroy it. I recently test drove a 2018 XLT with 50k and I was disgusted with the conditions of the interior. Trim peeling up and flaking off. It also drove poorly and the AC wasn’t functioning. Miles aren’t everything!

Other than that the turbos rattle, and I’m determined to find a solution to that asap.

TL;DR 10/10 I would buy again at this point in time. I got a great deal on it though and bought it before the used car market went stupid. With a 6-kid family my options are very limited, but this truck has been a blessing to us.

I've only got 58k miles on my 2018 XLT, but no cam phaser noise, no rattling, no seat collapsing, no shocks leaking.

The only issue I had was the cupholders falling out. Fixed that myself after the dealership said they needed to replace the entire console.

And then some "issues" that I suspect were the dealership rather than the truck: constantly telling me I need an alignment every time I bring it in for an oil change (I think their auto-alignment-detector thing was either broken or "optimized for revenue"), and they replaced my front differential without me asking or approving, saying "tech test drove it and heard front diff noise". I never heard anything, and I'm wondering if they were scamming Ford with a fake warranty repair. Anyway, I've never gone back to that dealership.

I drive like a grandpa (being one) so is it possible that driving habits affect how likely these issues are to happen to any given vehicle?

Coming from my 2006 which I liked, this one is twice as good and I wouldn't buy any other large SUV (unless they came out with an Excursion).

Meeker said:

I've only got 58k miles on my 2018 XLT, but no cam phaser noise, no rattling, no seat collapsing, no shocks leaking.

The only issue I had was the cupholders falling out. Fixed that myself after the dealership said they needed to replace the entire console.

And then some "issues" that I suspect were the dealership rather than the truck: constantly telling me I need an alignment every time I bring it in for an oil change (I think their auto-alignment-detector thing was either broken or "optimized for revenue"), and they replaced my front differential without me asking or approving, saying "tech test drove it and heard front diff noise". I never heard anything, and I'm wondering if they were scamming Ford with a fake warranty repair. Anyway, I've never gone back to that dealership.

I drive like a grandpa (being one) so is it possible that driving habits affect how likely these issues are to happen to any given vehicle?

Coming from my 2006 which I liked, this one is twice as good and I wouldn't buy any other large SUV (unless they came out with an Excursion).

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Thanks for sharing.

I am on the opposite end of the spectrum... I do have front diff noise, but dealer claims it is normal 4WD noise.