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Any experience with P0300?

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1
0
Exp. Type
HPDE
Exp. Level
Under 3 Years
Texas
Hey all, I'm new here and hoping to get some advice.

This past weekend I was driving at COTA and my CEL came on during the back straight between turns 11 and 12 (3rd and 4th gear, high load and RPM). After pitting in, I scanned the car and the only code present was P0300. I hadn't noticed any noticeable signs of misfire (power loss, shudder, etc) so I decided to clear the code and let the car cool off. After a few hours, I went back out and after a few laps I saw the CEL flickering. At this point, I reduced the throttle and started short shifting at 4 to 5k RPM. The light turned off and I was able to drive several more laps before calling it quits (the low fuel light came on around this time). I even drove the 60ish miles home without incident.

Currently, the light is off and the car has no noticeable drivability issues.

I'm wondering what y'all think of this. To me, the lack of a specific cylinder fault code leads me to believe it's not related to ignition. Maybe fuel or air delivery?

Car is a 2018 Mustang GT with PP1, bone stock minus an aftermarket catback.
 
11
0
Exp. Type
W2W Racing
Exp. Level
3-5 Years
United Arab Emirates
Hey all, I'm new here and hoping to get some advice.

This past weekend I was driving at COTA and my CEL came on during the back straight between turns 11 and 12 (3rd and 4th gear, high load and RPM). After pitting in, I scanned the car and the only code present was P0300. I hadn't noticed any noticeable signs of misfire (power loss, shudder, etc) so I decided to clear the code and let the car cool off. After a few hours, I went back out and after a few laps I saw the CEL flickering. At this point, I reduced the throttle and started short shifting at 4 to 5k RPM. The light turned off and I was able to drive several more laps before calling it quits (the low fuel light came on around this time). I even drove the 60ish miles home without incident.

Currently, the light is off and the car has no noticeable drivability issues.

I'm wondering what y'all think of this. To me, the lack of a specific cylinder fault code leads me to believe it's not related to ignition. Maybe fuel or air delivery?

Car is a 2018 Mustang GT with PP1, bone stock minus an aftermarket catback.
Hello there, I went through the same issue yesterday, the car was riding rough and I heard some noises as well but I'm not sure about the source as I have a loud exhaust, however the check engine didn't stay on, it started blinking when the car partially lost power on high RPM, I let off the gas pedal and in 15 to 20 seconds, the flashing stopped and the check engine light went off completely, I drove home and the car acted normally given that I wasn't beating on it, i plugged in the scanner and it gave me P0300 and P0050 as well.

So I'm wondering if you found the solution to this issue, or did you try troubleshooting it.

im driving a 2013 boss 302
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
You can misfire if the engine is not getting a stable enough supply of fuel (running low).
During Boss Track Attack the staff would fill the tanks 2-3 times per day. This was to ensure fuel was always available tot he pickup. If can be that simple.
 
11
0
Exp. Type
W2W Racing
Exp. Level
3-5 Years
United Arab Emirates
I actually had just a quarter of a tank, but I filled it up the day after, and I'm still facing the same issue. I read somewhere that adding an O-ring to the crank positioning sensor would solve this issue, and my mechanic recommended replacing the whole sensor since it's relatively cheap. However it only made it worse, now the RPM stops at 4k, and after 15 mins of driving it, the whole car started shaking, and it barely stayed on.
 
11
0
Exp. Type
W2W Racing
Exp. Level
3-5 Years
United Arab Emirates
Ford had a specific o-ring to use with the sensor. There should be a thread or two on the subject here. It’s been a while since I added the o-ring that I had forgotten about it.
I went and bought a brand new sensor and I found that it already comes with the o-ring unlike the one that's already on the car, I replaced it and it only got worse, and the car gave me few more errors saying that cylinders, 6,7, and 8 are misfiring.
it made me think whether the car needs to be programmed after replacing the sensor or its just a simple replacement.

NOTE that the spark plugs are 4 months old, so I don't think they're faulty, ill have them checked soon anyways.
 
I had these same issues. I changed to a new sensor with the o-ring and performed the crankshaft sensor relearn process with my SCT X4 and the problems have been fixed. No codes on any of the engine tunes I have available including the stock tune.
 
125
112
Exp. Type
HPDE
Exp. Level
Under 3 Years
Ann Arbor, MI
Timing, reprogramming needs to be done. The cam sensor could be the issue, it was on my mine. $13 part but timing etc needs to be completed - $275 out the door if you take it to your local Ford dealer - but it could fix it all. Good for the dealer to check this one with their obd’s imho.
 

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