Brand New 22’ Mustang GT flashing CEL

[br_an]

Anyone have any insight about the odd whining noise during idle/slow speeds (almost sounds like a supercharger?) It seems almost normal from some stuff I’ve seen online, or the cat changing color like that?

any help is very appreciated.

Is your car an Auto? I think the 10R80 has a known whine "feature"

https://www.mustang6g.com/forums/threads/2018-10r80-a10-most-recent-tsb’s-in-here.102918/post-2822562

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[ORRadtech]

Honestly a P0300 code by itself is far too nonspecific for any real diagnosis.
I'd let Ford clear the code and see if it comes back. If it were in conjunction with a P0301 through P0308 that would at least start to give a direction to look. As an aside any auto parts store will read your codes for free or you can get an inexpensive OBD dongle and read codes from your phone or I believe there's a way to read them through the dash. Pretty sure there's a how-to on that on the forum.
As for the cat, I've never looked at one with 300 miles on it so cannot comment if the color change is normal. But since their normal temp range is 1200-1600 degrees I'd bet it's fine. I've read that it takes around 2k degrees for them to suffer harm. You could always get an inexpensive infrared temp guage to check it after driving.
My '18 automatic doesn't make noise in park but it's a little noisy at low speeds but only really noticeable in parking garages. At one time the autos were coming from the factory low on transmission fluid so maybe have that checked.

 

[Cobra Jet]

P0300 is generic misfire code.

This thread may give you some enlightenment to Ford's misfire strategies:
https://www.mustang6g.com/forums/threads/good-tech-article-on-ford’s-misfire-strategy.108076/

Also here is a pdf snip from the Ford Shop manual. which is "Coyote" specific. I'm including it because it gives a bigger picture of how to diagnose misfire events from the generic to the actual cylinder event codes:.
https://www.mustang6g.com/forums/attachments/hd-misfire-detection-pdf.538665/

Check and make sure the crank sensor wire and connector are secure. A loose wire within the connector or the connector itself will throw a P0300.

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The discoloration of the exhaust - completely normal with any new vehicle. The exhaust metal won’t stay one color, it’s going to discolor and in some instances it will also get slight surface rust color.

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You have a brand new vehicle covered bumper to bumper for the first 3/36k. Then you have the Powertrain that covers 5/60k (but runs concurrently with the 3/36), and the Emissions Warranty which is 8/80k, and again runs concurrently with the 3/36 and 5/60. With that said, you’re covered for any repairs so if the code is bothering you, make an appointment.

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[Zelek]

Are you sure that's "normal"?? LOL
He got the code, it's a P0300 code.

Lol, I meant the coloration on the cat.

 

[Call_Me_Bruce]

P0300 is a random misfire. The computer is unable to detect which cylinder(s) are misfiring. CEL will flash with this code to tell you to back off because raw fuel is getting sent into the cats. Put some premium in it and drive it. If you pop another CEL take it back and make them fix it.

 

[22BlackGt]

Anyone have any insight about the odd whining noise during idle/slow speeds (almost sounds like a supercharger?) It seems almost normal from some stuff I’ve seen online, or the cat changing color like that?

any help is very appreciated.

P0300 is generic misfire code.

This thread may give you some enlightenment to Ford's misfire strategies:
https://www.mustang6g.com/forums/threads/good-tech-article-on-ford’s-misfire-strategy.108076/

Also here is a pdf snip from the Ford Shop manual. which is "Coyote" specific. I'm including it because it gives a bigger picture of how to diagnose misfire events from the generic to the actual cylinder event codes:.
https://www.mustang6g.com/forums/attachments/hd-misfire-detection-pdf.538665/

Check and make sure the crank sensor wire and connector are secure. A loose wire within the connector or the connector itself will throw a P0300.

—

The discoloration of the exhaust - completely normal with any new vehicle. The exhaust metal won’t stay one color, it’s going to discolor and in some instances it will also get slight surface rust color.

—

You have a brand new vehicle covered bumper to bumper for the first 3/36k. Then you have the Powertrain that covers 5/60k (but runs concurrently with the 3/36), and the Emissions Warranty which is 8/80k, and again runs concurrently with the 3/36 and 5/60. With that said, you’re covered for any repairs so if the code is bothering you, make an appointment.

—

Thanks!

i saw on another thread where you had posted a SSM about the whine noise in 2017-2020. Would you say that is still applicable to my situation? I have the 10R80.

 

[spedy7]

Hmmm...my '22 has also developed a rough idle at times but no CEL and no codes. Started happening around the 1k mile mark - being that these are essentially streetable race motors I was a little rough on break in after 300 miles (no oil consumption at 3400 miles ). Without a/c on it feels like it's missing a bit at idle, with the a/c on it'll drop a bit in RPM after ~30 seconds in neutral and really shake the car about. Always ran 91 until this past week having to drive to Cali - $6.72 for 87! I'm also really starting to hate the rev hang when pulling hard to 6k+ RPM in 2nd/3rd and shifting up...I'm just waiting for the clutch discs to explode.

I'd take a guess at the "revised" cats, MAF sensor, and PCM (detuned) calibration being the main culprits...but I'm no engineer lol. I'm also putting my 2 cents on the table - I'm starting to not trust any vehicle built after 2020 (mine included).

 

[Wickedluis]

Is your car a 10 speed? Those transmissions make whiny noise which I believe is normal .

 

[Cobra Jet]

Thanks!

i saw on another thread where you had posted a SSM about the whine noise in 2017-2020. Would you say that is still applicable to my situation? I have the 10R80.

Yea, the 10R80 when new does make a whine, it's similar to a 2003/04 Cobra supercharger whine on the down shift and when winding it out upshifting. The whine is attributed to how the gears are machined/cut. As the trans breaks in the whine actually starts to subside.


Check out the main 10R80 thread - within it are very informational docs and PDFs about the 10R80 itself, it's internals, how it works, etc. It is very good reading material for new 10R80 owners.

 

[Albertcado]

I would just drive it as it's meant to be driven, however you may choose to break it in just drive it like you want to. If there is an underlying issue you don't want to mask it or prolong it from showing up by "taking it easy". It will probably be better for you and the car for any major issues to show themselves while you drive the car spirited imo. That way you can have your dealership fix, repair, or replace whatever it is early on. They'll probably be more inclined to help since your car is super new too.

 

[Whitemare21]

I also had a random p0300 code at about 2100 miles. Took it to the dealer and they cleared it while advising me to watch if it reappears. At 6200 miles now and it has not reappeared since that day. At the time it happened, I was doing a pull while my gas light was on. Could of possibly been bad gas or the little amount of fuel was sloshed to the back of the tank and perhaps lost pressure? Either way, if the code has not reappeared for you, then I would say you are good to go. It happens and there are many possible factors.

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