P0107 on 2001-2005 Honda Civic (D17 Engine): MAP Sensor Circuit Low Input Causes and Fixes

What's Unique About the 2001-2005 Honda Civic

For the 7th generation Honda Civic (2001-2005), the P0107 code is a very common and straightforward issue. The MAP sensor is conveniently located directly on top of the throttle body, secured by two easily accessible Phillips head screws. 🎬 Watch: How to find and replace your Civic's MAP sensor. This makes it exceptionally easy to access and replace, even for a novice DIYer, often in under 15 minutes. Unlike some vehicles where the sensor is buried, on the Civic's D17 engine it's one of the simplest sensor replacements you can perform.

Symptoms You May Notice

• Check Engine Light is on
• Rough or surging idle
• Engine hesitation or stumbling during acceleration
• Poor fuel economy
• Engine stalling, especially at stops or when returning to idle
• Difficulty starting the engine, long crank times
• Black smoke from the exhaust (due to a rich fuel mixture)
• Engine may enter 'limp mode' with significantly reduced power
🎬 See a breakdown of common bad MAP sensor symptoms.

Most Likely Causes

1. Faulty Manifold Absolute Pressure (MAP) Sensor 🔴 High Probability → Shop Manifold Absolute Pressure Sensor The sensor is a very common failure item due to age and heat cycles on the D17 engine, typically failing after 100,000 miles. Forum consensus is that this is the cause over 90% of the time.
   How to confirm: With the key on, engine off, use a scan tool to read MAP sensor data. A reading below 0.5V or stuck at a low value confirms the issue. Alternatively, back-probe the sensor's signal wire (typically the middle wire, GRN/RED) with a multimeter. A reading below ~0.5V points to a bad sensor. 🎬 Watch: A professional guide to testing MAP sensor voltage. Given the high failure rate and low cost, simply replacing the sensor is the most common and effective diagnostic step.
   Typical fix: Replace the MAP sensor. It is held on by two Phillips head screws on top of the throttle body.
   Est. part cost: $20-$70
2. Wiring or Connector Issue ⚪ Low Probability Wiring can become brittle with age, but it's far less common than sensor failure for this specific code.
   How to confirm: Visually inspect the MAP sensor's three-wire connector for corrosion, damage, or loose pins. With the key on, use a multimeter to check for 5V reference voltage on the YEL/RED wire and a good ground (near 0V) on the GRN/WHT wire. If either is missing, the problem is in the wiring, not the sensor. Wiggling the harness while monitoring voltage can reveal intermittent breaks.
   Typical fix: Repair the damaged section of the wiring harness or clean/replace the connector pigtail.
   Est. part cost: $5-$25
3. Vacuum Leak Very Low Probability While possible, a vacuum leak large enough to cause a P0107 would typically present with other, more severe drivability issues and likely different codes. A vacuum leak typically causes higher than normal MAP voltage at idle, not lower.
   How to confirm: Listen for hissing sounds around the intake manifold with the engine running. A more reliable method is to use a smoke machine to introduce smoke into the intake system and watch for leaks. A vacuum leak is an unlikely cause for a 'circuit low' code, which points more directly to an electrical fault.
   Typical fix: Replace the cracked or disconnected vacuum hose.
   Est. part cost: $5-$20

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is extremely rare. The PCM should only be considered after the sensor, its connector, and the wiring harness have all been definitively ruled out. There are very few, if any, documented cases online of a PCM being the root cause for this specific code on this vehicle.

Diagnosis Steps

1. Read the code with an OBD-II scanner to confirm P0107 is present.
2. Visually inspect the MAP sensor, which is located on top of the throttle body, held by two Phillips screws. Check its 3-pin electrical connector for any signs of damage, corrosion, or looseness.
3. Inspect the wiring harness leading to the sensor for any visible damage, fraying, or breaks.
4. Easiest path for DIY: Given the extremely high probability of sensor failure, the most time-effective step is often to replace the sensor. It is inexpensive and takes minutes.
5. To confirm electrically: With the key in the 'ON' position (engine off), unplug the connector. Use a multimeter to test the harness-side connector terminals. You should find one with ~5 volts (reference power from the YEL/RED wire), one with ~0 volts (ground from the GRN/WHT wire), and the third is the signal return (GRN/RED wire).
6. If power and ground are good, the MAP sensor is faulty. Replace it.
7. If power or ground is missing, you have a wiring problem or, very rarely, a PCM issue. Trace the faulty wire back from the connector to find the break or short. The MAP sensor signal wire (GRN/RED) goes to pin A19 on the ECU.
8. After repair or replacement, clear the code with the scanner and perform a test drive to ensure the fix is complete.

Parts You'll Likely Need

• Manifold Absolute Pressure (MAP) Sensor (OEM #37830-PGK-A01) — This is the most common failure point for the P0107 code on this vehicle. The OEM manufacturer is Denso, and their part number is 079800-5410, which cross-references to the Honda part number.
  Trusted brands: Denso (OEM Manufacturer), NGK/NTK, Standard Motor Products (SMP), Delphi
  OEM price range: $60-$80
  Aftermarket price range: $20-$50

Related Codes That Often Appear With This One

• P0108 — P0108 is 'MAP Sensor Circuit High Input'. Seeing it intermittently with P0107 can indicate a failing sensor with erratic output or a loose connection/damaged wire that is shorting and opening.

Technical Service Bulletins (TSBs) & Recalls

• While no TSB exists specifically for P0107 on the 2001-2005 Civic, Honda TSB 04-073 for the S2000 addressed engine hesitation from MAP sensor connection issues, indicating a known sensitivity in Honda MAP sensor systems of that era.

Platform-Specific Known Issues

• Real-World Repair Story: A user on Reddit with a 2004 Civic experiencing both P0107 and P0108 codes after replacing the sensor twice was advised to check wiring. The advice was: 'Backprobing the wire is essential. Check grounds. Probe the sensor wire ground at the connector and put the other meter lead on the battery negative. You should have .1V or less of a voltage drop. If you have more, you have a ground wire problem.' This highlights that while rare, wiring issues can mimic a sensor failure.

Mechanic-Grade Diagnostic Values

• MAP Sensor 5V Reference Voltage — expected: ~4.5V to 5.0V DC. Failure: Voltage significantly below 4.5V or 0V indicates a wiring or PCM issue.
• MAP Sensor Ground Circuit Test (Voltage Drop) — expected: Less than 0.1V (100mV). Failure: Voltage higher than 0.1V indicates high resistance or a poor ground connection.
• MAP Sensor Signal Voltage (Key On, Engine Off) — expected: ~2.9V to 4.5V depending on atmospheric pressure.. Failure: Voltage below 0.5V triggers P0107.
• MAP Sensor Signal Voltage (Engine Idling) — expected: ~0.7V to 1.5V at normal operating temperature.. Failure: Voltage stuck low (near 0V) or high (near 5V) indicates a faulty sensor or vacuum issue.
• MAP Sensor Ground Wire Resistance to Chassis — expected: Near 0 Ohms (no resistance). Failure: Any significant resistance (e.g., above 10 Ohms) indicates a problem with the ground circuit.

Scan Tool Commands That Help

• Honda Diagnostic System (HDS): MAP Data List — To view the live voltage and pressure reading from the MAP sensor to see if it's stuck low, not changing with engine RPM, or reading erratically. This is the primary software-based diagnostic step.
• Honda Diagnostic System (HDS): Circuit Check for MAP PB Line — This is a guided diagnostic step within the HDS for troubleshooting P0107. It instructs the technician to check for continuity to ground, which helps identify a short circuit in the signal wire.

Wiring & Ground Locations

• MAP Sensor Connector (3-Pin) — On top of the throttle body.. This is the primary connection point. Pin 1 (YEL/RED) is 5V reference, Pin 2 (GRN/RED) is the signal, and Pin 3 (GRN/WHT) is the sensor ground.
• ECU Connector A, Pin A19 — At the Powertrain Control Module (PCM/ECU), typically located behind the glove box or in the passenger-side footwell.. This is the termination point for the MAP sensor signal wire (GRN/RED). Checking for continuity between the sensor connector and this pin can rule out a broken wire.
• ECU Connector A, Pin A21 — At the PCM/ECU.. This is the termination point for the 5V reference wire (YEL/RED) that powers the MAP sensor.
• ECU Connector A, Pin A11 — At the PCM/ECU.. This is the termination point for the MAP sensor ground wire (GRN/WHT).
• G101 — On the thermostat housing.. This is a primary engine ground point that provides the ground path for many sensors, including the MAP sensor circuit via the ECU. A corroded or loose G101 can cause various sensor codes, including P0107.

Real Owner Repair Stories

• Honda-Tech forum user (B16 engine swapped into a CRX, converted to OBD1 (similar MAP sensor principles)) — Code 3 (OBD1 equivalent of P0107/P0108), running very rich.
  ❌ Tried (didn't work) Replaced MAP sensor 3 different times, Swapped ECU, Hardwired all 3 wires from ECU to sensor
  ✅ What actually fixed it The user grounded the MAP sensor's ground wire directly to the chassis, which resolved the issue, indicating a fault in the ECU's internal ground for that circuit or a break in the original ground wire.

Model Year Variations Within This Range

• 2004-2005: The 2004-2005 models switched from a narrowband primary O2 sensor to a wideband Air/Fuel ratio sensor. While this does not directly affect the MAP sensor, it's a key difference in the engine management system of the D17A1/A2 engines within this generation. An issue with the A/F sensor could potentially cause confusing diagnostic symptoms alongside a MAP sensor code.
• 2001-2005: The D17A1 (LX/DX models, non-VTEC) and D17A2 (EX models, VTEC) engines were used. The MAP sensor and the P0107 fault are identical between them, but the D17A2 has additional VTEC-related components (solenoid, pressure switch) that are not present on the D17A1.

Diagnostic Flowchart

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0108 — MAP Sensor Circuit High Input. Often appears alongside P0107 on the 2001-2005 Civic when dealing with intermittent wiring/ground issues or a failing MAP sensor, as noted by owners on Reddit and AliExpress.
• P0106 — MAP Sensor Circuit Range/Performance. Another MAP sensor code that frequently accompanies P0107 when the sensor is failing or has carbon buildup, as reported by Civic owners.
• P0172 — System Too Rich. Directly related to the P0107 symptom of 'Black smoke from the exhaust (due to a rich fuel mixture)' caused by the ECU receiving incorrect manifold pressure data and over-fueling the engine.
• P0300 — Random/Multiple Cylinder Misfire Detected. Related to the severe drivability symptoms of P0107, such as rough/surging idle, engine hesitation, and stumbling during acceleration.

Frequently Asked Questions