DTC Troubleshooting: P0300 (71-1), P0300 (72-1), P0300 (73-1), P0300 (74-1)

DTC P0300 (7x-1):  Random misfire and any Combination of the Following:
DTC P0301 (71-1):  No. 1 Cylinder Misfire
DTC P0302 (72-1):  No. 2 Cylinder Misfire
DTC P0303 (73-1):  No. 3 Cylinder Misfire
DTC P0304 (74-1):  No. 4 Cylinder Misfire

NOTE:

1.Troubleshoot the following DTCs first if any of them were stored along with the random misfire DTC(s):
P0107, P0108: Manifold Absolute Pressure (MAP) sensor
P0131, P0132: Primary Heated Oxygen Sensor (Primary HO2S) (Sensor 1)
P0171, P0172: Fuel system
P0335, P0336: Crankshaft Position (CKP) sensor
P1361, P1362: Top Dead Center (TDC) sensor
P1519: Idle Air Control (IAC) valve

2.Test-drive the vehicle to verify the symptom.

3.Find the symptom in the chart below, and do the related procedures in the order listed until you find the cause.

Symptom Procedure(s) Also check for: 
Random misfire only at low engine speed and under load Check fuel pressure. 
  • Low compression.
  • Low quality fuel.
 
Random misfire only during acceleration Check fuel pressure.  
Random misfire at high engine speed, under load, or under random conditions Check fuel pressure. Correct valve clearance.