Check engine light blinking and running poorly at idle

NickBaragona

Recently replaced all ignition coils and an O2 sensor that was throwing a code. All codes associated with that cleared from the permanent codes section of the ECU and my Z was running perfect for 100 miles or so.

Then recently I went to start it and the check engine light started blinking immediately. I noticed a loss of acceleration, like it’s in limp mode.

I’m at a loss because the only code being thrown now is P0300.

I have replaced :
Spark Plugs
Ignition Coils
1 O2 sensor

I do have an uprev cable for monitoring, just not sure where I should start.

Not sure if this would have anything to do with the issues but the car has not been driven a lot over the years. It is a 2010 and just crossed 50k miles.

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