Jts 2.0 engine? First code if I remember correctly is for the engine immobiliser failure. This code can come up when the immobiliser fails to read from the key just once and will stay in ecu history until cleared. Nothing to worry about unless it happens often.
The 0300/0301 relate to misfire on coil 1. 0300 is generic misfire code and 0301 is misfire coil 1. Coil 2 would be 0302 etc..
This could be bad coil, bad spark plug, bad wiring, bad injector, oil down spark plug well(caused by careless oil top-up)or just gremlins at start up as was the case with my jts.
Mine would bring up engine light and motor control system failure message when starting on cold mornings but would be fine within seconds and extinguish the engine light but store the code.
After changing coil and spark plugs and cleaning up electrical connections it still happened but the car drove great so it didn't really bother me.
Try clearing the codes and see if they come back
Yes, mine is a GT 2.0 JTS
I had logged these from torque installed to my Andriod phone. during recording, when ecu is beeping, torque data will halt as well.
It happens most on big step of gas but car is in a high gear where engine load is high, uphill in high gear more etc.
I had cleared the code before, I had the MAF cleaned and changed to another used one. I had the battery charged up after last clear code, at first the code doesn't come back as often, only occasionally, but after I put the car down for a week, the drive were beep most of the time, therefore, I suspect a weak battery. but torque told me I have 13V when driving..
Second thought, do I have wiring problems? since torque data from BT ODB adapter should not halt at any time, does this meant ecu is having short signal? but if it is short, it should happen regularly through out my drive, not giving more warnings during uphill in high gear..
Third is the coil, is this cheap to replace all coil and spark plugs?
Or I should replace the battery first? Volt is good, maybe amp is not good! no idea
Code from Torque
Dash Error Display
During drive Error Code Video