Some sensor faults appear for a second and then vanish. The check engine light comes on after a bumpy road, then the car runs fine for days. A P0114 code means the intake air temperature signal dropped out or jumped for a moment, and the engine computer noticed.
Intermittent faults take patience to track down. This guide shows you how the code sets, what causes it and how to catch the problem while it happens.
P0114 Code Breakdown
Every OBD-II code follows the same five-character pattern set by the SAE J2012 standard. Each character narrows down which system has the fault. This table shows what each part of the code tells you.
| Character | Meaning | What It Tells You |
|---|---|---|
| P | Powertrain | The fault is in the engine or transmission systems. |
| 0 | Generic (SAE) code | The definition is the same on every OBD-II vehicle. |
| 1 | Fuel and air metering | The fault involves the sensors that measure air and fuel. |
| 14 | Specific fault | Intake Air Temperature Circuit Intermittent |
What the P0114 Code Means for Your Engine
The SAE J2012 standard defines the P0114 code as Intake Air Temperature Circuit Intermittent. The intake air temperature (IAT) sensor is a thermistor that changes resistance with air temperature.
Real intake air temperature changes slowly. The powertrain control module (PCM) expects the IAT signal to do the same. When the reading jumps from normal to -40°F or 300°F and back in a split second, the PCM knows the circuit lost contact or shorted for a moment.
Because the fault comes and goes, the sensor may test fine in your driveway. That makes this code harder to diagnose than a steady high or low fault.
Symptoms of an Erratic IAT Signal
Symptoms of a P0114 code show up only while the signal acts up. Many drivers see only the warning light. Look for these signs:
- Check engine light that turns on and off
- Brief stumble or hesitation while driving
- Rough idle that comes and goes
- Problems that get worse over bumps or in wet weather
- Other temperature or MAF codes stored at the same time
Write down when the symptoms happen. Notes about weather, engine temperature and road conditions help a lot.
Common Causes of the P0114 Code
Loose and worn connections cause most intermittent temperature faults. These are the usual causes:
- Loose connector. A connector that is not fully locked loses contact as the engine moves.
- Spread or corroded terminals. Worn pins grip poorly and lose contact over bumps.
- Chafed wiring. A wire rubbing on a bracket can short or open briefly.
- Broken wire inside the insulation. The copper may separate only when the wire flexes.
- Moisture in the connector. Rain or a car wash can cause brief shorts.
- Failing IAT sensor. A cracked thermistor may work only some of the time.
How to Find the Cause of a P0114 Code
The key is to make the fault happen while you watch. A scan tool that can graph live data makes this much easier.
Graph the IAT Reading
Start the engine and graph the IAT reading. A healthy signal moves in a smooth, slow line. Sudden spikes to -40°F or drops to very high temperatures point to a circuit problem.
Check the freeze frame data from when the code set. It shows engine speed, load and temperature at that moment. Try to drive under the same conditions while you watch the graph.
Do a Wiggle Test
With the engine idling and the graph running, gently wiggle the IAT connector. Then flex the wiring one short section at a time, following it toward the PCM. A spike on the graph marks the problem area.
If the IAT sensor is built into the mass air flow (MAF) sensor, wiggle that connector too. Tapping the sensor body lightly can reveal a bad internal connection.
Check the Pins
Turn the engine off and unplug the connector. Look for corrosion, bent pins and a broken locking tab. Check that each terminal grips a matching test pin firmly. A single loose pin causes many intermittent faults.
Fixes for a Dropping IAT Signal
Repair the fault you found, clear the P0114 code and drive under the conditions that used to set it. These are the most common fixes:
- Reseat and lock the connector. Make sure the tab clicks into place.
- Clean the terminals with electrical contact cleaner, then add dielectric grease to the seal.
- Replace worn terminals or the pigtail when pins no longer grip.
- Repair chafed or broken wires with solder and heat shrink tubing, then secure them.
- Replace the IAT sensor, or the MAF sensor if the IAT sensor is built in, when the wiring checks out.
Typical Repair Costs
Finding the fault often takes more time than fixing it. Here are typical price ranges.
| Repair | DIY Cost | Typical Shop Cost |
|---|---|---|
| Connector cleaning | $10 to $15 | $50 to $100 |
| Terminal or pigtail replacement | $15 to $40 | $100 to $200 |
| Wiring repair | $10 to $30 | $100 to $300 |
| Standalone IAT sensor | $15 to $60 | $75 to $150 |
| MAF sensor with built-in IAT | $80 to $350 | $150 to $500 |
Related Codes
These codes often show up with this one or point to the same system:
| Code | Meaning |
|---|---|
| P0111 | Intake Air Temperature Circuit Range/Performance Problem |
| P0112 | Intake Air Temperature Circuit Low Input |
| P0113 | Intake Air Temperature Circuit High Input |
| P0115 | Engine Coolant Temperature Circuit Malfunction |
| P0116 | Engine Coolant Temperature Circuit Range/Performance Problem |
Stopping an Erratic IAT Signal for Good
A P0114 code means the intake air temperature signal drops out or jumps for short moments. Loose pins and damaged wires cause most cases.
- Note when the symptoms happen.
- Graph live data and do a wiggle test.
- Repair connectors and wiring before you replace the sensor.
- Confirm the fix under the same conditions that set the code.
Frequently Asked Questions
Can I Drive with a P0114 Code?
You can usually drive normally, since brief IAT dropouts rarely affect how the engine runs for long. The PCM switches to a default value when it sees a bad reading. Still, an intermittent fault often gets worse, so plan the repair before it turns into a constant failure.
Why Does the Code Appear Only When It Rains?
Rain and car washes let water reach a connector with a worn seal. Water can bridge the pins for a moment and cause a short. Once the connector dries, the signal returns to normal. Cleaning the pins and adding dielectric grease to the seal usually fixes this pattern.
Can a Bad Ground Cause Intermittent Temperature Readings?
A loose or corroded sensor ground can make the IAT signal jump. On many engines, the IAT sensor shares a ground circuit with other sensors, so several readings may glitch at once. Check the engine ground straps and the PCM ground connections if more than one sensor acts up.
Will Clearing the Code Fix the Problem?
Clearing the code only turns off the check engine light. The fault is still there, so the code returns the next time the signal drops out. Keep the freeze frame data before you clear anything, since it shows the conditions that triggered the fault and speeds up the diagnosis.