Cylinder 7 misfire replaced new plug & wires, new fuel pump & filter, new crank shaft position sensor what else could be causing it
My Thoughts
- Understanding what causes an engine misfire
- Burnt/bent valve
- faulty fuel injector
- loss of compression on that cylinder
According to the Manual
Code P0307 System Description
The engine control module (ECM) uses information from the crankshaft position sensor (CKP) in order to determine when an engine misfire is occurring, and uses information from the camshaft position sensor (CMP) in order to determine which cylinder is misfiring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM is able to detect individual misfire events. If the ECM detects a misfire rate can be high enough to cause the catalytic converter to overheat, possibly damaging the converter. The malfunction indicator lamp (MIL) will flash ON and OFF when catalytic converter overheating conditions are present and DTC P0300 is set. DTCs P0301-P0308 corresponds to the cylinders 1-8. If the ECM is able to determine that a specific cylinder is misfiring, the DTC for that cylinder will also set.
Code P0307 Conditions for Running the DTC
- DTC P0100, P0011,P0101, P0102, P0103, P0106, P0108, p0116, P0117, P0118, P0128, P0220, P0335, P0336, P0502, P01258, P3401, P3425, p3441, an P3449 are not set.
- The engine speed is between 650-6,200 RPM.
- The ignition voltage is between 11-18 volts.
- Engine coolant temperature (ECT) is between 19 and 266 F.
- The fuel level is more than 10 percent.
- Antilock brake system (ABS) and the traction control system (TCS) are not active.
- The power management is not active.
- The transmission is not changing gears.
- The ECM is not fuel shut-off, or decel cut-off mode.
- Excessive drive wheel slip is not detected.
- Power Take Off is disabled.
- Cylinder Deactivation is not in progress.
- A manual transmission with a throttle position less than 95 percent.
- DTC P0300-P0308 runs continuously when above conditions are met.