DTC P0300: Random Misfire & With DTC P0301-DTC P0306

NOTE: If misfire is in one cylinder only, see DTC P0301, P0302, P0303, P0304, P0305 or P0306: MISFIRE IN ONE CYLINDER .

NOTE: If DTCs P0107, P0108, P0131, P0132, P0171, P0172, P0401, P0505, P1128, P1129, P1259, P1361, P1362, P1366, P1367, P1491, P1498 and/or P1519 is stored, troubleshoot these codes before trouble shooting random misfire DTCs.

If DTC P0300 is set with DTC P0301, P0302, P0303, P0304, P0305 or P0306, test drive vehicle. Based on misfire conditions, test vehicle in order listed. For random misfire only at low RPM and under load, check for:
- Insufficient fuel pump flow or pressure.
- Low engine compression.
- Poor fuel octane level quality.
For random misfire only during acceleration, check for:
- Insufficient fuel pump flow or pressure.
- Ignition coil malfunction.
- VTEC system malfunction.
For random misfire only at high RPM, under load, or under random conditions, check for:
- Insufficient fuel pump flow or pressure.
- Ignition coil malfunction.
- Incorrect valve clearance.
Repair as necessary.
If misfire is intermittent or does not recur during test drive, check for improper fuel octane level (less than specification), or carbon deposits on spark plugs.