P0300 code

[tukn20s]

When I'm driving above 85mph the check engine light starts flickering. Doesn't just stay on, just flickers. Once I slow down it stops. Driving in the streets the check engine light has not come on. Mind you, the light doesn't come on all the time above 85mph. Has anyone experienced this before? Could it be that not enough fuel is reaching the cylinders or air? Any suggestions would be helpful. This started happening in the past month and has only happened maybe 2-3 times. Thanks

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[Knacht]

There is a thread on a flickering CEL just the other day here.
I think the conclusion was that it is a cylinder missfire.

 

[ORRadtech]

There is a thread on a flickering CEL just the other day here.
I think the conclusion was that it is a cylinder missfire.

Well, yeah, that's what P0300 is. Random misfires.
Random misfires can be caused by a whole bunch of different things. Fuel, air, vacuum, timing (vvt) are just a few of them.
OP, your best next step is to get some live data. Hook up a good bidirectional scan tool and get some data.
Also, the more information you can provide the more likely we are to be able to help. Is your car stock, or modded? If modded, what mods? Tuned, by who? Milage, fuel you're using, etc?
Finally, driving with a flashing CEL is dangerous for engine safety. For example, if it's running lean you risk damage to pistons, valves and catalytic converters.

 

[tukn20s]

I have a power pack 2, corsa full exhaust, 58k miles. I have always used 76gas 91 octane.
Question, I have been driving and the light has not come on, will this still be damaging my car?
Thanks for your help.

 

[ORRadtech]

I have a power pack 2, corsa full exhaust, 58k miles. I have always used 76gas 91 octane.
Question, I have been driving and the light has not come on, will this still be damaging my car?
Thanks for your help.

Generally speaking no cel should mean you're fine. But you're talking to some random guy over the internet who has no way of knowing what is happening with your car. You should be fine but who knows?
My best suggestion for you is to contact your tuner and/or a good local mechanic that understands modified cars.

 

[Cobra Jet]

A random genetic code like the P0300 is a PIA and no one on here would be able to give you a definitive "it's this part".

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/

However, here's some things you can check:

Check the connector at the MAF and make sure it's totally secured. Make sure you don't have any breaches along the air intake track, or any cracks damages to the intake. Any such breach before or after the MAF is a vacuum issue and will skew signals for incoming air flow monitoring.

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Pull the plugs and post images of what you find for their readings/condition.

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- VCT solenoids - if the solenoids are not operating properly due to debris or they are failing due to age, they can cause such codes. Quite a few threads on here about these prematurely failing and/or how to diagnose.

The culprit here was the VCT solenoid::
https://www.mustang6g.com/forums/th...s-and-cam-retarded-codes.176734/#post-3571964

Here's (2) more threads for VCT info that I had previously posted in other threads:
https://www.mustang6g.com/forums/threads/2015-2021-s550-5-0’s-ssm-50067-vct’s-again-various-dtc-codes.169419/

https://www.mustang6g.com/forums/threads/p0018-code.123932/

- 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

There is the crank relearn and it has to be done exactly as noted (some people have had to do it 2 or 3x) as well as trying KAM reset too. Here’s a thread I had with details of the crank relearn and KAM resets.
https://www.mustang6g.com/forums/threads/engine-misfire-problems.203556/#post-4075889

The IMRC design has been problematic since the IMRC intake system first debuted in the 1994 Lincoln MKVIII with the 4.6 DOHC (which was then carried into the 1996 Cobra and beyond). Theres MANY threads on here regarding the intake and IMRC system.
https://www.mustang6g.com/forums/threads/possibly-broken-imrc-shaft.183221/#post-3689879

Clutch pedal or brake pedal bumpers deteriorated or missing. It’s a known issue, Ford issued a. NHTSA recall and if either is deteriorated or missing it will cause non-start or drivability issues with the car.
https://www.mustang6g.com/forums/th...edal-bumper-nhtsa-recall.172153/#post-3670904

and
https://www.mustang6g.com/forums/threads/brake-light-switch-near-pedal-failure.122100/

Ignition coils:
If you’re getting a common or steady P030x (specific cylinder) then it could be a failing ignition coil pack. To determine this, if you have a P0304 for example, swap the Cyl 3 and Cyl 4 ignition coils - see if you now get a P0303 instead of a P0304…. If you do, it’s a faulty coil pack.

Hope something above was helpful.

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