P0113 Code: Toyota Tacoma (2016-2023) - Causes, Symptoms & Fixes

Comprehensive diagnostic guide for OBD-II code P0113 on 2016-2023 Toyota Tacoma

Data note and limitations

• The provided real-world data for this model/year shows: No NHTSA owner complaints found for this make/model/year/issue combination. No recalls found in the NHTSA database.
• Because there are no complaints or recalls in the dataset, this guide relies on general automotive knowledge for the P0113 code and applies it to the Tacoma’s likely engine setups (2.7L 4-cylinder and 3.5L V6) with caveats for engine-specific layout.
• If you have access to live data from a scan tool, use it to confirm specifics for your exact engine and year. This guide focuses on practical, broadly applicable steps for Tacoma owners.

CODE MEANING AND SEVERITY

• Code meaning (P0113): Intake Air Temperature (IAT) Sensor Circuit High Input. The PCM is reading a higher-than-expected voltage from the IAT sensor circuit, suggesting the sensor is reporting an unusually high intake air temperature, or there is a fault in the circuit.
• What it affects: The IAT reading helps the PCM adjust fuel trim and ignition timing. A consistently high IAT input can cause the engine to run lean or rich depending on the calibration, which can degrade drivability and fuel economy.
• Severity in practical terms: Moderate. Most modern Toyotas will still run, but you can expect MIL illumination, possible rough idle, hesitations, reduced throttle response, and lower fuel economy until the fault is repaired. Severe drivability impacts (stalling, limp mode) are less common but possible if the PCM reacts strongly to the faulty input.

COMMON CAUSES ON TOYOTA TACOMA

• Faulty IAT sensor: The sensor itself is defective and reports an abnormally high temperature reading.
• Wiring harness/connectors: Damaged, corroded, loose, or oil/condensation-contaminated IAT wiring or connectors can create a high-input signal.
• Short to power or ground: A bare wire contacting battery voltage or ground can push the IAT circuit high.
• PCM input circuit fault: Less common, but valuation of the PCM’s analog input could be degraded.
• Sensor location/installation issues: If the sensor is damaged or not seated properly (especially on models with IAT integrated into the intake tract), readings can go high.
• Contamination or oil in the intake path: Excess oil or other contaminants near the sensor can affect readings or the sensor’s surface.
• Environmental/air intake changes: Consistently very hot intake conditions or rerouted/intake air routing modifications can intermittently produce high readings if the sensor is affected by unusual routing or heat soak.
• Intermittent data/aging: With age, wiring insulation can harden or connectors can corrode, causing intermittent high readings.

SYMPTOMS YOU MIGHT notice (in addition to MIL)

• Check Engine Light (MIL) or a stored P0113 on an OBD-II scanner.
• Slight to moderate loss of throttle response or hesitation during acceleration.
• Reduced or fluctuating idle quality.
• Possible change in fuel economy (often worsened).
• In some cases, the vehicle may run normally if the fault is intermittent or if the PCM has compensating strategies.

DIAGNOSTIC STEPS (practical, Tacoma-focused)

Note: Always start with a visual inspection and then proceed to electrical tests. Disconnect the battery only if you’re comfortable with clearing codes, and reconnect after work.

Step 1: Confirm and gather data

• Use an OBD-II scanner to confirm P0113. Note freeze-frame data: engine temperature, IAT reading, throttle position, engine RPM, etc.
• Check for any accompanying codes (P0110, P0111, P0112, P0114, or others) that might indicate related sensor or circuit problems.

Step 2: Visual inspection

• Inspect the IAT sensor and its wiring/connector for obvious damage, corrosion, water intrusion, oil contamination, or loose connections.
• Look for signs of chafed wires along the wiring harness to the sensor, especially where the harness can rub on intake components.
• Check for aftermarket air intake modifications that could affect sensor routing or heat soak.

Step 3: Electrical checks (P/N: power, ground, and signal)

• Key-on, engine off: check continuity and resistance of the IAT circuit wiring from the PCM pin to the IAT sensor ground and to the 5V reference (as applicable to your engine’s IAT circuit). This tests for opens or shorts in the harness.
• Key-on, engine off: verify the 5V reference supply to the IAT circuit (if your vehicle wiring diagram shows a PCM 5V reference to IAT). Backprobe the sensor connector to confirm a stable reference and grounding path.
• Engine-running live data test: with the engine running and at operating temperature, monitor the IAT sensor signal voltage (or resistance, depending on your scanner). For a typical NTC IAT with a 5V reference, signal voltage should vary smoothly with intake temperature (often something like a lower voltage when cold and a higher voltage as it warms up). Any readings that sit abnormally high or don’t drift with temperature changes indicate sensor or circuit fault.

Step 4: Inspect the IAT sensor itself

• If available, remove the IAT sensor (or the sensor in the intake tract) and compare readings to cold-start and warmed conditions using a heat chamber or warming source, or use a known-good sensor for a cross-check.
• When removing, inspect the sensor for signs of contamination or damage to the sensing element.

Step 5: Test the IAT sensor in-use

• If the sensor resistance range is known for your engine (consult service data for your exact engine), compare measured resistance to expected values at known temperatures. If readings are inconsistent with temperature, replace the sensor.
• If the 5V reference or ground is failing, or the PCM input is momentarily reading abnormally due to a short, repairing or replacing wiring or the PCM pin may be required.

Step 6: Clear codes and re-test

• After performing repairs, clear the codes and run the vehicle through a few drive cycles to confirm P0113 does not return. If the fault reappears, re-check wiring and consider PCM-related inspection.

Step 7: When to replace

• Sensor test shows the IAT sensor is faulty or readings do not respond to temperature changes.
• Wiring harness shows damage, corrosion, or a short to power/ground.
• PCM input is suspected after thorough harness testing and no fault found in the sensor/wiring.

RELATED CODES

• P0110: MAF sensor circuit (or related mass airflow sensor wiring) — different sensor, but sometimes other intake-system faults can co-occur.
• P0111: IAT circuit range/performance (the sensor or circuit is outside normal range without a clear “high input” condition).
• P0112: IAT sensor circuit low input (sensor reading too low, opposite fault condition).
• P0114: IAT circuit intermittent (intermittent signal loss or corruption).
• Depending on the exact engine, there could be model-specific variants of IAT-related codes, but the core concept remains IAT sensor circuit integrity.

REPAIR OPTIONS AND COSTS (2025 prices)

Notes:

• Prices are approximate ranges based on typical U.S. market pricing for 2025. Regional differences and labor rates will vary.
• No recalls found in NHTSA database for this issue on 2016-2023 Tacoma (per dataset).

DIY options (typical workflow)

• IAT sensor replacement part: $15–$60
• Additional materials (new O-ring/seal if required, dielectric grease): $5–$15
• Tools: basic hand tools; no specialty tools required in most cases
• Labor: 0.5–1.0 hour (your time)
• Estimated total DIY cost: about $20–$75 (parts + incidental materials)

Professional repair options

• IAT sensor replacement (parts + labor): $70–$180 total
  • Parts: $20–$60
  • Labor: 0.5–1.0 hour at typical shop rates (around $90–$150 per hour depending on region)
• Wiring harness or connector repair (if fault found in wiring)
  • Parts: $10–$80 (depending on harness segments)
  • Labor: 1.0–2.0 hours
  • Estimated total: $100–$300
• PCM-related fixes (rare)
  • Parts: may involve PCM replacement or reprogramming
  • Labor: 1.0–3.0 hours
  • Estimated total: $200–$600 (plus potential calibration costs)
• Note: If diagnostics identify a more complex issue (eg, a bad connector or a harness route that caused chafing), the cost will reflect the extra teardown steps.

DIY VS PROFESSIONAL

• DIY advantages: Lower cost, learning experience, and quick sensor replacement if you’re comfortable with basic automotive electrical work; can be done in a few hours.
• DIY drawbacks: Risk of misdiagnosis if you don’t verify wiring, 5V reference, and signal integrity; improper reassembly can cause further issues.
• Professional advantages: Comprehensive diagnostic approach, proper test equipment, and accurate fault isolation; potential to identify collateral issues (eg, harness damage not visible at first glance).
• Professional drawbacks: Higher cost, downtime while awaiting service, potential discretionary labor charges for diagnostics.

PREVENTION

• Regular maintenance: Replace air filters on schedule to ensure clean intake air and minimize potential sensor contamination.
• Inspect intake plumbing: Periodically check for cracks, loose hoses, or heat soak issues near the IAT/air intake path.
• Keep connectors clean and dry: Ensure the IAT connector is clean and firmly seated; apply dielectric grease if recommended by the service manual to resist corrosion.
• Avoid oil/antifreeze contamination: Ensure PCV and related systems aren’t leaking oil or coolant into the intake region, which could contaminate sensors.
• Address issues early: If a MIL comes on, don’t ignore it. Early diagnosis can prevent more extensive or expensive repairs later.
• Regional considerations: In dusty or humid environments, pay extra attention to wiring harness protection and corrosion resistance.

If you’re facing P0113 on a 2016-2023 Toyota Tacoma, use the above steps as a structured diagnostic approach. Start with a visual check and electrical tests of the IAT circuit, verify the sensor’s readings with live data, and proceed to replacement only after confirming the fault source. And remember: the dataset indicates no NHTSA complaints or recalls for this exact issue in this model/year, so this guide is focused on typical troubleshooting and common-sense repair practices. If you have access to model-specific service data or TSBs, incorporate those steps as needed.