P0106 on 2011-2015 Ford Explorer 2.0L EcoBoost: MAP Sensor and Wiring Fault Guide

What's Unique About the 2011-2015 Ford Explorer

On the 2.0L EcoBoost engine family, this code is specifically addressed by Ford Technical Service Bulletin (TSB) 13-7-5. While the TSB officially names the 2013 Escape, the 2.0L GTDI engine architecture and its issues are shared across platforms like the Explorer. The TSB indicates the cause is often not the sensor itself, but corrosion in the connector for the boost pressure sensor (also called a MAPT or TCBP sensor) or a fault in shared wiring splices (specifically splice S108 for the MAP and S182 for the TCBP on the 2.0L GTDI). This makes a thorough wiring and connector inspection, including a 'wiggle test' of the harness, a critical first step, as simply replacing the MAP sensor may not fix the problem.

Symptoms You May Notice

• Check Engine Light is on
• Rough or unstable idle
• Hesitation or stumbling during acceleration
• Noticeable loss of engine power or entering 'limp mode'
• Reduced fuel economy
• Engine stalling, especially at idle
• Hard starting or crank-no-start
• "Engine Fault Service Now" message may appear on the dash

Most Likely Causes

1. Wiring Harness or Connector Corrosion 🔴 High Probability TSB 13-7-5 specifically identifies corrosion in the Turbocharger Boost Pressure (TCBP/MAPT) sensor connector and faults in shared wiring splices (S108, S182) as a primary cause for this code on 2.0L GTDI engines. These engines were used in the Explorer and other models, which experienced the same issue.
   How to confirm: Visually inspect the connectors and wiring harness for both the MAP sensor on the intake manifold and the boost pressure sensor for any signs of green or white corrosion, backed-out pins, or physical damage. Perform a 'wiggle test' on the harness near the splices while monitoring sensor data on a scan tool to see if the readings fluctuate.
   Typical fix: Clean the corroded terminals using a specialized contact cleaner. If corrosion is severe, the connector pigtail may need to be replaced. Repairing the faulty wiring splice (crimp and solder) is often required per the TSB.
   Est. part cost: $15-$50 for a connector pigtail
2. Faulty Manifold Absolute Pressure (MAP) Sensor 🟡 Medium Probability → Shop Manifold Absolute Pressure Sensor The MAP sensor is a common failure point for this code on many vehicles. The 2.0L EcoBoost uses multiple pressure sensors, and either the one on the intake manifold (post-throttle) or the boost pressure sensor (pre-throttle, often called TCBP) could be at fault.
   How to confirm: With a scan tool, monitor the MAP sensor voltage with the Key On, Engine Off (KOEO). It should read close to the BARO sensor reading and be around 4.5-5.0V at sea level. At idle, it should drop to 1-2V. If the readings are stuck, don't match the BARO at KOEO, or do not change with engine RPM, the sensor is likely bad.
   Typical fix: Replace the faulty MAP sensor. The primary one is located on top of the intake manifold and is easily accessible.
   Est. part cost: $40-$115
3. Vacuum Leak ⚪ Low Probability Any unmetered air entering the engine after the throttle body will cause the MAP sensor reading to be inaccurate compared to what the PCM expects. Hoses can become brittle over time. NHTSA ODI #10967364 describes a scenario where plastic tubing failed by "disintegrating" in the vicinity of an engine part, leading to P0106.
   How to confirm: Visually inspect all vacuum hoses connected to the intake manifold for cracks, brittleness, or loose connections. A smoke test is the most effective way to find small, hard-to-see leaks.
   Typical fix: Replace the cracked or broken vacuum hose or intake gasket.
   Est. part cost: $5-$50

Rare But Worth Checking

• Clogged Catalytic Converter: A severely restricted exhaust can increase backpressure, affecting the intake manifold pressure reading. This is usually accompanied by a severe loss of power, especially at high RPMs, and potentially other exhaust-related codes.
• Faulty Powertrain Control Module (PCM): This is extremely rare and should only be considered after all other possibilities (sensors, wiring, vacuum leaks) have been exhaustively ruled out by a professional.
• Altitude-Related Transport Faults: Manufacturer service bulletins SSM 50156 and SSM 49446 note that some Ford vehicles may store P0106 after being transported to higher altitudes while in transport mode or after key-off transportation. Clearing the DTC and driving the vehicle typically resolves this specific condition.

Diagnosis Steps

1. Scan for any other accompanying trouble codes. Pay special attention to P0236, as this points towards the TSB-identified wiring issue.
2. Inspect the Wiring: Carefully examine the wiring and electrical connectors for both the MAP sensor on the intake manifold and the Turbocharger Boost Pressure (TCBP/MAPT) sensor located on the charge pipe before the throttle body. Look for corrosion, loose pins, or damage as described in TSB 13-7-5.
3. Perform a Harness Wiggle Test: With the key on and engine off, monitor the MAP and TCBP sensor PIDs on a scan tool. Lightly push and pull on the engine harness in the areas of splice S108 and S182 (as shown in TSB diagrams) and watch for any erratic jumps in the pressure readings.
4. Check for Vacuum Leaks: Inspect all vacuum lines and the intake air system for cracks, loose fittings, or damage. A smoke test is the most reliable method to find hidden leaks.
5. Test the Pressure Sensors: Use a scan tool to observe live data from both the MAP and TCBP sensors. With the key on and engine off (KOEO), their readings should be nearly identical to the Barometric Pressure (BARO) sensor reading. At idle, the MAP sensor reading should drop significantly (1-2V), while the TCBP reading will remain high. If a sensor's voltage is static or doesn't respond correctly, it may be faulty.
6. Replace the Faulty Component: If a sensor fails the test, replace it. If wiring is corroded, clean or replace the connector pigtail. If a wiring splice is confirmed to be faulty, repair it using a solder and heat-shrink method. If a vacuum leak is found, repair it.
7. Clear Codes and Test Drive: After the repair, clear the trouble codes with a scan tool and perform a test drive to ensure the P0106 code does not return.

Parts You'll Likely Need

• Manifold Absolute Pressure (MAP) Sensor (OEM #BB5Z-9F479-C) — This is one of the primary sensors that can fail and cause this code. It is located directly on the intake manifold. This part number supersedes previous versions BB5Z-9F479-A and BB5Z-9F479-B.
  Trusted brands: Motorcraft, Bosch, Standard Motor Products, NTK
  OEM price range: $65-$115
  Aftermarket price range: $40-$80
• Turbocharger Boost Pressure (TCBP) Sensor (OEM #AG9Z-9F479-A) — Also referred to as the MAPT or pre-throttle MAP sensor, this sensor's circuit is often the root cause of the wiring issue described in TSB 13-7-5. It is located on the charge pipe leading to the throttle body.
  Trusted brands: Motorcraft, Bosch
  OEM price range: $50-$90
  Aftermarket price range: $30-$60
• MAP Sensor Connector Pigtail (OEM #WPT-1050 (Motorcraft)) — TSB 13-7-5 points to corrosion in the sensor connectors as a common cause. If cleaning doesn't work, the pigtail must be replaced. This pigtail fits the TCBP sensor.
  Trusted brands: Motorcraft, Dorman
  OEM price range: $25-$50
  Aftermarket price range: $15-$30

Related Codes That Often Appear With This One

• P0236 — This code for 'Turbocharger Boost Sensor A Circuit Range/Performance' is often seen with P0106 because, as noted in TSB 13-7-5, they can share the same faulty wiring splices or connector issues.
• P0069 — This code for 'Manifold Absolute Pressure - Barometric Pressure Correlation' can appear alongside P0106 as it also compares pressure sensor readings for rationality. On some Ford platforms, a PCM update was issued to correct over-sensitive P0069 triggers.

Technical Service Bulletins (TSBs) & Recalls

• TSB 13-7-5: Addresses drivability concerns and DTCs P0106/P0236 caused by corrosion in the TCBP/CACT/MAPT sensor connector or wiring concerns in signal return splices S108 and S182 for the 2.0L GTDI engine.
• SSM 50156: Notes that vehicles may exhibit an illuminated MIL with DTC P0106 stored after key-off transportation to higher altitudes.
• SSM 49446: Indicates that vehicles may exhibit an illuminated MIL with DTC P0106 while in transport mode, especially in higher altitudes.

Platform-Specific Known Issues

• TSB 13-7-5 was issued for 2013 models with the 1.6L and 2.0L GTDI engines for DTC P0106, indicating a known issue with wiring splices or connector corrosion on the pressure sensors. The 2.0L engine shares this design flaw with the Explorer.
• A separate TSB summary also links P0106 on 2013-2014 Explorers

Mechanic-Grade Diagnostic Values

• MAP/TCBP Sensor Signal Voltage, Key On Engine Off (KOEO) — expected: ~4.5V - 5.0V (at sea level, should correlate with BARO reading). Failure: Voltage is stuck low (e.g., <1.0V), high, or does not match the BARO sensor's equivalent reading. A difference of >1.5 psi (10.35 kPa) is a failure threshold per some TSBs.
• MAP Sensor Signal Voltage, Engine Idling (post-throttle body) — expected: 1.0V - 2.0V. Failure: Voltage remains high (near KOEO reading) or does not drop, indicating the sensor is not reading engine vacuum.
• TCBP Sensor Signal Voltage, Engine Idling (pre-throttle body) — expected: Stays high, close to KOEO reading (~4.5V). Failure: Voltage drops significantly at idle, which is not expected for a pre-throttle sensor.
• Sensor 5V Reference at Connector — expected: ~5.0 volts. Failure: No voltage or significantly low voltage points to a wiring or PCM issue.
• Sensor Ground Circuit Resistance — expected: < 1.0 Ohms to a known good ground. Failure: High resistance indicates a poor ground connection, which can cause erratic sensor readings.
• MAP Sensor Pressure Range (2.0L EcoBoost) — expected: Operates between ~23 kPa (on overrun) and ~270 kPa (under full boost).. Failure: Sensor readings that are stuck or do not plausibly track with engine load and throttle changes.

Scan Tool Commands That Help

• Ford IDS / FORScan: Datalogger / Live Data — Use this to record and graph the PIDs for MAP, TCBP, BARO, Throttle Position, and RPM simultaneously. Perform a 'wiggle test' on the harness or a test drive and watch for any signal dropouts or irrational readings that correlate with the movement or engine load. This is the primary method for catching intermittent wiring faults.
• Ford IDS / FORScan: KOEO and KOER Self-Tests — Run these tests to allow the PCM to perform a comprehensive check of its inputs. This can sometimes flag related codes that haven't yet illuminated the CEL and can help differentiate between a hard fault (fails KOEO) and an intermittent one (may only fail during KOER or a test drive).
• Ford IDS / FORScan: Mode $06 Data Analysis — Check Mode $06 for test IDs related to the MAP and pressure sensors. This can show test results and limits that are not available in standard live data, potentially revealing a sensor that is close to failing its threshold but not yet setting a hard code consistently.

Wiring & Ground Locations

• Splice S108 — In the engine wiring harness. Per Safety Recall 14S17, it is located in the same harness section as S182. It is a two-wire into four-wire splice with Yellow/Green wires.. This is the signal return splice for the MAP sensor. A fault here, as identified in TSB 13-7-5, is a primary cause of P0106. The repair involves cutting out the old splice and re-soldering the connections.
• Splice S182 — In the engine wiring harness, near S108. It is a one-wire into two-wire splice with Gray/Brown wires.. This is the signal return splice for the TCBP (boost) sensor. A fault here causes P0236 and can contribute to the rationality check failure that triggers P0106. The repair is often performed at the same time as S108.
• G104 / G105 / G106 — These are primary engine compartment ground points. G104 is typically on the left front of the engine compartment, while G105/G106 are on the left and right sides of the engine compartment, respectively.. The MAP and TCBP sensors rely on a clean ground connection for accurate readings. The signal return wire (which fails at S108/S182) eventually goes to ground. A loose or corroded main ground can cause floating voltages and erratic behavior across multiple sensors, including the ones that trigger P0106.
• MAP Sensor Connector Pins — On the sensor itself, located on the intake manifold.. For testing, you need to identify the 5V reference, ground, and signal wires. While specific pin numbers can vary, you can identify them with a multimeter: one pin will have ~5V, one will have ~0V (ground), and the third is the signal wire whose voltage changes with pressure.

Real Owner Repair Stories

• SHO Forum user (Ford with 3.5L GTDI (uses similar MAP logic)) — P0106 code appeared after changing the engine tune.
  ❌ Tried (didn't work) Disconnecting the battery for 30 minutes.
  ✅ What actually fixed it The issue was caused by an aftermarket 4-bar MAP sensor that was installed for a custom tune. When the owner reverted to the stock tune, the PCM's expectations no longer matched the aftermarket sensor's output. Reinstalling the original OEM 2-bar MAP sensor resolved the P0106 code.
• NHTSA ODI #10787972 — An owner reported that due to diagnostic trouble codes P0106 and P0236, the engine experienced hesitation, loss of idle RPM, difficulty in starting, and a lack of power. The report references manufacturer bulletins TSB 13-9-8 and TSB 13-5-29.

OEM Part Supersession History

• BB5Z-9F479-A, BB5Z-9F479-B → BB5Z-9F479-C — Revision and improvement of the MAP sensor.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Power Transfer Unit (PTU) Failure 🔴 High — Common, especially over 60,000 miles. Caused by overheating of the 'lifetime' fluid due to proximity to the exhaust.
• Internal Water Pump Failure (3.5L V6 Engine) 🔴 High — Very common on the 3.5L V6 engine around 70,000-120,000 miles. The pump is internal and timing chain-driven; failure can cause coolant to mix with engine oil, leading to catastrophic engine damage.
• Exhaust Odor In Cabin 🟠 Medium — Widespread complaints across 2011-2017 models. Investigated by NHTSA but did not result in a full recall. Ford issued TSBs (e.g., 16-0166) to seal body gaps and reprogram HVAC. (Ref: TSB 16-0166)
• EVAP Canister Purge Valve Failure 🟡 Low — A common cause for EVAP leak codes (like P0456) and hard starting after refueling. The part is relatively inexpensive and easy to replace.
• Carbon Buildup on Intake Valves 🟠 Medium — Inevitable on all direct-injection engines like the 2.0L EcoBoost over time (typically noticeable after 80,000+ miles), leading to reduced performance and misfires. Requires walnut blasting to clean.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For this repair, using used parts is generally not recommended. The primary causes are wiring fatigue/corrosion and sensor failure, both of which are risks with used electronic components.

Donor-vehicle mileage cap: roughly under 40000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• If pulling a connector pigtail, inspect for any signs of green/white corrosion inside the connector.
• Ensure the wiring insulation is not brittle, cracked, or previously repaired.
• Avoid parts from vehicles with visible signs of flood or heavy engine bay water damage.

OEM-only on this vehicle (don't cheap out):

• Manifold Absolute Pressure (MAP) Sensor
• Turbocharger Boost Pressure (TCBP) Sensor

Aftermarket brands forum-validated for this vehicle:

• Bosch (often the OEM supplier)
• NTK
• Standard Motor Products (SMP)

Brands owners have reported issues with on this vehicle:

• No-name, unbranded sensors from online marketplaces. These often have poor calibration and a high failure rate, leading to the code returning.

Real Owner Stories

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

Related OBD-II Codes

• P0236 — This code often accompanies P0106 and points specifically toward the wiring issues and sensor corrosion identified in TSB 13-7-5.
• P0069 — A pressure sensor correlation code known to affect the 2.0L EcoBoost platform, often addressed alongside P0106 via sensor replacement or PCM updates.
• P0456 — An EVAP leak code mentioned as a common issue for this vehicle, often caused by a faulty canister purge valve which can also lead to hard starting.

Frequently Asked Questions