Any ideas for a p0300:00-ed code?

[ronnyek42]

2018 mustang GT pp2. Car is taken care of and bone stock and only had 10k mi on it.

Recently, I've started getting a check engine light and codes related to misfires.

Today check engine engine came back as a p0300:00-ed code indicating random misfire.

Last time I read codes I saw something about battery voltage indicating it was 10v or less but that hasn't come back.

Anyone have any ideas? I don't have a warranty anymore because of the age... But I am mechanically inclined and have decent scan/service tools.

I could fire parts cannon at it getting new plugs and making sure I am putting in high quality fuel... But that seems like it's just a guess.

Are imrc or whatever still a problem on the 2018s or only a problem with previous gen?

Thanks for anything that might help me figure it out

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[Cobra Jet]

2018 mustang GT pp2. Car is taken care of and bone stock and only had 10k mi on it.

Recently, I've started getting a check engine light and codes related to misfires.

Today check engine engine came back as a p0300:00-ed code indicating random misfire.

Last time I read codes I saw something about battery voltage indicating it was 10v or less but that hasn't come back.

Anyone have any ideas? I don't have a warranty anymore because of the age... But I am mechanically inclined and have decent scan/service tools.

I could fire parts cannon at it getting new plugs and making sure I am putting in high quality fuel... But that seems like it's just a guess.

Are imrc or whatever still a problem on the 2018s or only a problem with previous gen?

Thanks for anything that might help me figure it out

P0300 is just a generic code and is difficult to determine exact cause of the DTC. Here's some info below for you to peruse - rather than just throwing parts. I would suggest reading up about Ford Misfire strategy linked below and the excerpt from the shop manual.

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 an older 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 VCTs, O2 sensors, the crank sensor, ground wires, and all wiring harness connectors in the engine bay to make sure the connections are secure. This thread below has the info for VCT's and crank sensor:
https://www.mustang6g.com/forums/th...n2-coyote-with-60k-miles.177596/#post-3586437

DIY to cycling debris from VCT's:
https://www.mustang6g.com/forums/threads/rpm-drops-on-2019-gt.175505/page-4#post-3593500

This thread has the info for the O2:
https://www.mustang6g.com/forums/threads/p0300-issues-after-imrc-lockout.178809/#post-3607516

- Crank sensor - failure can be the sensor itself, the harness to it or the pins in the connector. If the crank sensor is failing, it also will throw various misfire DTCs. The only time the crank sensor will throw a specific crank DTC is if the sensor is disconnected or it has completely failed. Many have found even with a generic misfire P0300, that the issue was related to the crank sensor. These sensors do not last forever due to their location and under hood heat cycles.
Check this thread:
https://www.mustang6g.com/forums/threads/misfire-at-high-rpm.174380/#post-3531453

AND this one:
https://www.mustang6g.com/forums/th...e-sensor-tone-ring.156234/page-2#post-3197692

IMRC failure is commonplace too and can cause a generic P0300 - there's many threads on here about that, easy to search "IMRC".

The above are most common sources that can cause the very generic P0300....

 

[K4fxd]

Put a new battery in it.

 

[ronnyek42]

I just hooked up my scan tool and monitored misfire events... I noticed that while running if I did mild acceleration revs, I noticed it oculd record misfire events pretty quickly and it seemed like when it did the intake sound was.... different... but I don't know.

Is IMRC still a thing for 2018's+. Almost every reference I've seen to people complaining about it said 2015-2017.

these are the previous codes I was getting before I cleared them a few days ago

U3003:16-08 - Battery voltage from instrument panel control module

and

P0300:00-ED Random misfire
P0302:00-65 Misfire detected in cylinder #2
P0304:00-65 Misfire detected in cylinder #4
P0305:00-65 Misfire detected in cylinder #5

 

[K4fxd]

I'll say it again, put a new battery in it. These cars hate low voltage and they do strange things. Since you got a battery low voltage code I'd start there.

 

[Rob911]

I have a 2022 gt auto PP1 and am experiencing a misfire at 1,250 rpms that is very noticeable at around 70 km/h (42 mph). Basically coast down to 70 km/h then reapply very light throttle and feel the shudder. I have also gotten the occasional "car is in sleep mode" when it shouldn't be. They ran some diagnostics and told me that it came back with the battery at 63 percent... but that does not mean that the battery has only 63 percent charge they said. (Seems to me that this is exactly what it means...)

They replace the plug for cylinder #1 which was misfiring and swapped the coils for cylinder 1 and 2. I took delivery three months ago and she is going back in for another service on Monday for more troubleshooting. It's always done this since new.

 

[K4fxd]

she is going back in for another service on Monday for more troubleshooting.

It's pretty well documented that Ford uses shit batterys in the mustangs. 63%???, I'd put a new one in. I'll bet it fixes your problems.

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