P0113 on the 6.4L Power Stroke is an intake air temperature (IAT) sensor circuit high input fault. The IAT sensor measures the temperature of air entering the engine so the PCM can adjust fueling, timing, and regeneration strategy. When the PCM reads an IAT voltage that is too high, which corresponds to an implausibly cold temperature, it stores P0113.
Intake air temperature may seem like a minor input, but the 6.4L uses it to tune cold-start fueling, injection timing, and the regeneration strategy that keeps the diesel particulate filter clean. When the PCM believes incoming air is far colder than it really is, it can add fuel that is not needed, which shows up as smoke and reduced economy. Correcting P0113 restores accurate air data so the engine runs and regenerates the way it was calibrated to.
What P0113 means
The IAT sensor is a thermistor whose resistance changes with temperature. High resistance produces high signal voltage, which the PCM interprets as very cold air. P0113 sets when that voltage stays at the high end of the scale, pointing to an open circuit, a disconnected sensor, or a failed sensor element.
Common causes
- Open or broken IAT signal or ground wire
- Disconnected or corroded IAT connector
- Failed IAT sensor (often integrated with the intake air or MAF assembly)
- Chafed harness rubbing through insulation
- Water or corrosion in the connector
Symptoms
- Check engine light, often with little drivability change
- Hard cold starts or extended crank
- Slightly rough running or excess smoke on startup
- Reduced fuel economy
- Regeneration strategy affected in cold conditions
How to diagnose it
View live IAT data with a scan tool. A reading pinned at an extreme cold value, such as well below ambient, confirms the high circuit fault. Inspect the connector for corrosion and a secure fit, then back-probe the sensor. With the key on, a good sensor circuit shows a mid-range voltage; a value stuck high suggests an open. Check the signal wire and ground for continuity back to the PCM, and measure sensor resistance against a temperature chart if in doubt.
How to fix it
Repair open or chafed wiring and clean or replace a corroded connector, which fixes many P0113 cases. If the wiring and ground are good but the sensor reads out of range, replace the IAT sensor. On the 6.4L the sensor may be part of a combined intake air assembly, so confirm the correct part before ordering. Clear the code, verify the IAT reading matches ambient temperature at a cold start, and road test. For the correct IAT sensor or intake air assembly, contact sales@coredieselparts.com.
Frequently asked questions
Is P0113 serious on a 6.4L Power Stroke?
It is usually mild in terms of drivability, but incorrect air temperature data can hurt cold starts, smoke, and economy. Fix it to keep fueling and regen strategy accurate.
Can cold weather trigger P0113?
Genuine cold does not set the code, but an open circuit reads as impossibly cold. If the code appears in mild weather, the sensor or wiring is the cause, not the temperature.
How much does an IAT sensor cost to fix?
The sensor itself is inexpensive, and often the real fix is a wiring or connector repair. Contact sales@coredieselparts.com for the correct part for your 6.4L.
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