I have a 2020 mustang gt premium convertible with a stage 2 whipple. I inherited it from my dad and it's very sentimental to me. He tried to trade it in and was declined because it was throwing codes. He took it to a trusted mechanic who couldn't find anything wrong. I'm getting codes P0307
P0316
P0420. Any help would be appreciated. I can give more info but my knowledge is limited.

 

The P0307 code stands for “Cylinder #7 Misfire Detected,” which means there's an incomplete combustion happening inside cylinder #7, causing it to misfire. A bad ignition coil, a faulty injector, and an internal engine problem are some possible causes of the P0307 code
A P0316 code means that your vehicle's main computer, the Power Control Module (PCM), has sensed a misfire in one or more of the engine's cylinders right after startup.
P0420 code signals a low catalyst system efficiency. This code suggests that the oxygen levels are below the desired threshold (Bank 1), which most often results from problems with your car's exhaust or fuel systems.

If the mechanic can't find anything wrong and you have these codes, then try someone else. There is a misfire condition - and that misfire on #7 may be triggering the other codes. Since your knowledge is admittedly limited, probably better off taking it to someone else to diagnose what is causing the misfire. Hopefully when the Whipple was installed a proper tune was done at the same time.

 

I have a similar issue, a 2017 Mustang Gt. I get random codes all for misfires. Engine runs the same, code p \300 and at times different cylinder numbers added to that p 301, p 308, p 305. No one ive taken it to can find any issues. Thinking of changing all the coils and plugs to start. Hate just guessing. Oh the light turns itself off most of the time.
Any insight is appreciated