The 2003 Ford Expedition, especially with the Triton engines, had a range of issues that could cause the symptoms you described. The OBD scanner codes are giving a broad range of possible faults, and while they can certainly point you in the right direction, it's also possible that a more straightforward issue is preventing the vehicle from starting.
Fuel Pump Relay: A common problem on these Expeditions is a faulty fuel pump relay on the fuse board. This would prevent the fuel pump from priming and sending fuel to the engine, resulting in a no-start condition. You can sometimes hear the fuel pump priming (a short humming sound) when you turn the key to the 'On' position before cranking. If you don't hear this sound, the fuel pump or the relay could be the issue. Swapping the relay with another identical one in the fuse box (like the horn relay) can be a quick test.
Battery Drain: If the battery drained immediately after turning off the vehicle, there might be an electrical problem or a parasitic drain. Ensure the alternator is working correctly and the battery gets recharged while driving. A weak battery might still crank the engine but not provide enough power for a successful start.
Misfire Codes: If the OBD scanner reported misfire codes, it could be due to spark plugs, coils, or even fuel delivery problems. If the vehicle has been sitting for a while before you purchased it, old gasoline could also be a factor.
Other Codes: The "hego" likely refers to the HO2S (Heated Oxygen Sensor), "purge" might refer to the EVAP purge valve, and "EGR" to the Exhaust Gas Recirculation system. While these are important for optimal running and emissions, they usually won't prevent the car from starting unless there's a significant underlying issue.
Next Steps:
Fuel Pressure Test: This will confirm if the fuel pump is providing the required pressure.
Battery Test: Ensure the battery is fully charged and can hold a charge.
Spark Test: Check if there's a spark at the spark plugs.
Check Timing: If the timing chain or belt slipped, it could cause misfires and a no-start condition.
Aug 21, 2023 at 1:42 PM
