2002 Ford F250 Super Duty miss firing when cold
Check your intake gaskets by spraying a water mist from an old spray bottle on them when the engine is running. Sometimes heat will expand the gaskets and seal them. When you find the leak, the engine RPM will change or the engine will stall.
Sparkplugs will do this when they are going bad. So will glowplugs on Diesel engines.
Also have your Battery checked. If the battery is weak, you will start at a low voltage and then as the Alternator catches up, the engine will get smoother when electric power is restored. The controls on your engine work off of Voltage readings so some controls will automatically set up controls bercause of the wrong Voltage for the condition.
Cold start circuit. Your engine will step up the idle and enrichen the fuel mix when a temperature sensor tells the controls that the engine is cold. There can be 2 temperature sensors and you want to check the sensor that operates the engine, not the dash gauge. You can tell which is the dash gauge by unplugging the sensor after the engine has warmed up(Running). When you lose your dash gauge, then you know that the other sensor is the one you want.
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