99 5.4 Expedition issues

P0401 - EGR Flow Insufficient Detected The EGR system is monitored during steady state driving conditions while the EGR is commanded on. The test fails when the signal from the DPF EGR sensor indicates that EGR flow is less than the desired minimum.

• Vacuum supply
• EGR valve stuck closed
• EGR valve leaks vacuum
• EGR flow path restricted
• EGRVR circuit shorted to PWR
• VREF open to DPF EGR sensor
• DPF EGR sensor downstream hose off or plugged
• EGRVR circuit open to PCM
• VPWR open to EGRVR solenoid
• DPF EGR sensor hoses both off
• DPF EGR sensor hoses reversed
• Damaged EGR orifice tube
• Damaged EGRVR solenoid
• Damaged PCM

P1299 - Cylinder Head Over Temperature Protection Active Indicates an engine overheat condition was detected by the cylinder head temperature (CHT) sensor. An FMEM Strategy called Fail-safe Cooling was activated to cool the engine.

• Engine cooling system concerns
• Low engine coolant level
• Base engine concerns

P0300 - Random Misfire The random misfire DTC indicates multiple cylinders are misfiring or the PCM cannot identify which cylinder is misfiring.

• Camshaft position sensor (CMP)
• Low fuel: less than 1/8 tank
• Stuck open EGR valve

P0443 - EVAP Control System Canister Purge Valve Circuit Malfunction The PCM monitors the EVAP canister purge valve circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified purge duty cycle by PCM command.

• VPWR circuit open
• EVAP canister purge valve circuit shorted to GND
• Damaged EVAP canister purge valve
• EVAP canister purge valve circuit open
• EVAP canister purge valve circuit shorted to VPWR
• Damaged PCM

P1451 - EVAP Control System Canister Vent Solenoid Circuit Malfunction Monitors the canister vent (CV) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified canister vent duty cycle by PCM command.

• VPWR circuit open
• CV solenoid circuit shorted to PWR GND or CHASSIS GND
• Damaged CV solenoid
• CV solenoid circuit open
• CV solenoid circuit shorted to VPWR
• Damaged PCM

P1309 - Misfire Monitor Disabled When the misfire monitor is disabled, usually due to the input signal generated by the camshaft position (CMP) sensor, by sensing the passage of teeth from the CMP wheel.

• Camshaft position sensor
• Powertrain control module
• ECT, MAF, and CKP sensors

with the codes you have here I would look in the direction of the egr valve first because that will cause the bucking and stalling, and the misfires, but so will the canister vent solonoid. the misfire codes and the cylinder overtemp code could be from overheating or because if the misfires.