guys my service engine came on randomly upon start up after leaving it parked overnight there was a quick fast stutter/shake that lasted maybe 5-7 seconds then the car felt normal right away.They pulled the code for me @ auto zone and said it was the Mass Air Flow Sensor. This morning i gassed up and right after i started my car the light went away. Could of it just been a false alarm ? was it my gas cap? gas cap was replaced fairly recent. If it is was the gas cap why did they pull code PO300 and PO301?. Should I replace the sensor ? any advised would be highly appreciated.

2010 G37x

 

Their description of the code is WRONG. This is an ignition misfire code.
The code that the ECU gives is the SYMPTOM not the cause.

It was not your gas cap, as that is a different code.
Wait and see if the code comes back.

 

the car has been running smooth after that day the code disappeared. Not sure what to do just leave be i guess?

 

Yes, relax and just drive it... Right now there is no issue and it would be difficult to troubleshoot.

If the car was very low on gas, it might be possible for a misfire to occur which can make the engine stumble.

 

gas cap would not set a p0301 or a p0300 fault code. p0301 is misfire in cylinder 1 and p0300 is random misfires. i have no clue why the morons at autozone would tell you it an air mass problem. just wondering why you replace a gas cap, was it lost?

 

hey guys thanks it was not a gas cap proplem maybe it wasen't tighten properly or possibly the fact i used 89 gas instead 91 or above becasue shortly after gassing up with 93 premium the light went out