Fuel Delivery

Gold ChapterATLAS-FUELDELI-0143Template 2.2

P0106

Manifold Absolute Pressure Circuit Range/Performance

P0106 applies to the Manifold Pressure / Engine Load Sensing system. The monitored item is manifold absolute pressure (MAP)/barometric pressure rationality system. The code's wording matters because it describes MAP circuit range/performance or pressure plausibility error; it does not by itself prove…

SeverityMedium to high
DriveabilityModerate to High if load calculation is badly skewed
Diagnostic Time1.0-2.5 hours
Typical Cost$100-$2,500+ depending on whether the proven fault is wiring, a sensor/actuator, or internal/mechanical engine work
Atlas StatusGold Chapter
Reviewed2026-08

Diagnostic Snapshot

Most Common Cause: MAP sensor connector/wiring fault or poor terminal contactEngine Damage Risk: Low to Moderate; severe fueling or boost errors can create additional riskSafe to Drive: Usually suitable only for limited driving when the engine runs normally and no severe warning signs are present. Diagnose promptly.Professional Scan Tool: Recommended; strongly recommended for Gold-level performance/correlation diagnosisMechanical Test Recommended: Yes when scan/circuit results indicate a physically abnormal condition; use the system-appropriate independent testDIY Difficulty: Advanced DIY / Professional preferred

Atlas Academy

Learn the System

Before diagnosing this code, it helps to understand the system behind it.

Read Understanding Fuel Delivery Systems

Technical Summary

P0106 — Manifold Absolute Pressure Circuit Range/Performance — is a Gold-tier Atlas chapter covering manifold absolute pressure (MAP)/barometric pressure rationality system. The failure description is MAP circuit range/performance or pressure plausibility error. The PCM is not merely checking whether a part exists; it is evaluating MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior.

Monitor logic is manufacturer-calibrated. The test may be suspended when voltage is unstable, prerequisite sensors are invalid, temperature is outside the monitor window, engine speed/load is unsuitable, or another fault prevents a meaningful comparison. That is why freeze-frame and companion codes are diagnostic evidence rather than administrative details.

The fastest path is to prove the fault category before buying parts. Compare map to baro key-on/engine-off where the design permits and then watch map response to start-up and throttle changes. From there, compare commanded versus actual behavior when available, verify circuit integrity using the correct wiring diagram, and then test the mechanical system only when the data points there.

Do not invent universal voltage, resistance, pressure, temperature, or duty-cycle specifications for manifold absolute pressure (MAP)/barometric pressure rationality system. Sensor technology and PCM pull-up/driver design vary. Use the service manual's connector view, pinout, expected PID behavior and test specifications for the exact vehicle.

Safety and risk: Moderate to High if load calculation is badly skewed. Engine/catalyst risk is Low to Moderate; severe fueling or boost errors can create additional risk. A flashing MIL, severe misfire, overheating, timing-chain noise, reduced-power condition with unreliable throttle response, or evidence of lost mechanical timing changes the recommendation from 'diagnose soon' to 'stop driving and verify the cause.'

Professional diagnosis becomes especially valuable when P0106 is intermittent or when scan data and physical symptoms disagree. A graphing bidirectional scan tool can show whether the PCM command precedes the actual response; a scope can show electrical dropouts or cam/crank phase; and smoke, vacuum, temperature or mechanical tests can establish whether the sensor is reporting reality.

After the repair, verification must target the original failure logic. Clearing the MIL is not proof. Recreate the freeze-frame neighborhood when safe, run the appropriate monitor, confirm related data remains plausible, and check both current and pending DTC memory. A repair that merely delays P0106 for one idle period is not finished.

What You'll Learn

  • How the PCM interprets MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior and why the wording of P0106 separates circuit faults from performance/correlation faults.
  • How to use freeze-frame and live data to decide whether manifold absolute pressure (MAP)/barometric pressure rationality system is electrically wrong or reporting a genuine mechanical condition.
  • How to plan power/ground/reference/driver testing without inventing universal specifications.
  • How to choose an independent physical test—waveform, smoke, vacuum/pressure, temperature or mechanical timing—when scan data alone cannot prove the root cause.
  • How to verify the repair by re-running the original monitor instead of relying only on a cleared MIL.

Think Like a Technician

Treat P0106 as a test result, not a parts order. First ask what the PCM had to believe before it was allowed to run this monitor. Then ask whether the evidence points to an electrical limit, a rationality disagreement, or a mechanical response problem.

For this code, the monitored evidence is MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior. If related data is invalid, fix that foundation first. If related data is trustworthy, reproduce the test and watch cause-and-effect: PCM command, circuit response, physical response, and feedback.

When the data and the symptoms disagree, verify reality with an independent measurement. A scan PID is what the module believes; a pressure gauge, thermometer, vacuum reading, oscilloscope waveform, physical timing check, or direct circuit test can show whether that belief is correct.

What This Code Means

P0106 applies to the Manifold Pressure / Engine Load Sensing system. The monitored item is manifold absolute pressure (MAP)/barometric pressure rationality system. The code's wording matters because it describes MAP circuit range/performance or pressure plausibility error; it does not by itself prove that the named component has failed.

The PCM is monitoring MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior. Exact enabling criteria and failure thresholds are calibration-specific. Typical prerequisites include stable module voltage, valid related sensor signals, and an operating state in which the PCM can reasonably judge the circuit or system. OEM service information takes priority over generic assumptions.

Electrical and mechanical paths must be separated. Vacuum leaks, blocked map port, incorrect cam timing, low compression, egr flow, boost-control faults, or intake restrictions can produce a believable electrical signal that is mechanically wrong. A good diagnostic plan uses freeze-frame, live data, circuit testing and a physical verification test to decide which path is actually responsible.

A Gold-level diagnosis should separate three questions: is the input or actuator electrically valid, is the mechanical system physically doing what the PCM expects, and are the enabling conditions valid enough for the monitor to make a fair comparison? That distinction prevents a common failure mode in OBD diagnosis: replacing the component named in the DTC without proving whether the PCM is reporting an electrical defect, a rationality problem, or a mechanical response problem.

System Overview

Manifold Pressure / Engine Load Sensing is part of the PCM's larger strategy for load calculation, combustion control, emissions and component protection. Manifold absolute pressure (map)/barometric pressure rationality system supplies feedback or receives a command that influences how the engine is operated.\n\nA useful way to diagnose this system is to separate input, command, physical response and feedback. The PCM may command a change; the circuit must carry that command; the mechanical system must respond; and one or more sensors must report that response. P0106 identifies where that chain no longer meets the calibrated expectation.\n\nShared causes matter. A poor module ground, weak system voltage, contaminated fluid, intake leak, mechanical timing fault or damaged common harness can create several apparently unrelated DTCs. Related codes should be interpreted together rather than treated as separate parts failures.

Why This Code Sets

The monitor for P0106 runs only when the PCM has enough trustworthy information to evaluate manifold absolute pressure (MAP)/barometric pressure rationality system. The exact enabling criteria are not universal; calibration may consider ignition state, time since start, RPM/load, temperature, voltage, other sensor validity and whether another DTC has disabled the test.

Once enabled, the PCM evaluates MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior. P0106 sets when that evidence remains outside the calibrated expectation long enough, often after one or more test samples or drive cycles depending on manufacturer strategy. The important diagnostic point is that the failure logic matches the wording: MAP circuit range/performance or pressure plausibility error.

A circuit-high/low/open type code should push circuit integrity higher on the list. A range/performance or correlation code often means the signal is electrically believable but does not agree with physical reality or another trusted input. A timing over-advanced/retarded code means commanded-versus-actual movement and oil/mechanical control deserve attention.

Do not invent a threshold from another vehicle. Two engines using similar sensors may have different pull-up voltages, actuator duty strategies, airflow models, timing targets or rationality windows. Use the exact service information when the diagnosis reaches specification-level testing.

Common Symptoms

  • Check Engine Light
  • Possible failed emissions inspection
  • Driveability symptoms depend on how strongly the fault changes load, timing, temperature or throttle control
  • Possible reduced power, roughness, hesitation, hard starting or fuel-economy change depending on the system
  • Fail-safe strategy may substitute a default value or disable an actuator

Most Likely Causes

  • 1. MAP sensor connector/wiring fault or poor terminal contact
  • 2. Blocked, contaminated, cracked, pinched, or disconnected MAP sensing port/hose where used
  • 3. Sensor reference/supply or ground circuit problem
  • 4. Biased or failed MAP sensor
  • 5. Vacuum leak or throttle/intake condition causing genuinely abnormal manifold pressure
  • 6. Incorrect valve timing, low compression, EGR flow, exhaust restriction, or boost-control fault creating a real pressure plausibility problem
  • 7. PCM calibration or input rationality issue after primary causes are eliminated

Freeze Frame Clues

  • System voltage: unusually low voltage can corrupt sensor/actuator behavior and should be corrected before chasing secondary faults
  • Engine speed and load: shows whether the fault occurred at idle, cruise, acceleration, deceleration, or start-up
  • ECT and IAT: establish warm-up state and whether temperature-based enabling criteria were likely satisfied
  • System-specific PIDs for Manifold Pressure / Engine Load Sensing: commanded versus actual values are more useful than the DTC alone
  • Throttle position and calculated load: help judge whether airflow/pressure/position readings were physically plausible
  • Fuel trims and O2/A/F data when airflow or load calculation is involved: identify lean/rich consequences rather than proving the named sensor failed
  • Vehicle speed and time since start: help reproduce intermittent wiring, heat-soak, or warm-up conditions
  • Companion codes: correlation, reference-voltage, misfire, oil-pressure, throttle-correlation or temperature codes can change test priority

Live Data Expectations

Graph MAP with BARO, throttle position, RPM and calculated load. Key-on/engine-off MAP should be logically consistent with atmospheric pressure for the design; after start-up on a naturally aspirated gasoline engine it should reflect manifold vacuum and then move promptly toward atmospheric pressure as the throttle opens. If the electrical signal moves smoothly but manifold pressure itself is abnormal, test the engine/intake system rather than condemning the sensor.

Typical Verification Tests

  • Re-scan after repair and confirm P0106 is absent from current and pending memory.
  • Repeat the operating condition shown in freeze-frame when safe and legal.
  • Graph the key Manifold Pressure / Engine Load Sensing PIDs and confirm the response is smooth, plausible and consistent with the PCM command or physical condition.
  • Perform a wiggle/heat-soak verification if the original fault was intermittent.
  • Run any manufacturer-required relearn, adaptation or crank/cam variation procedure after component or timing work.
  • Complete the applicable OBD monitor/readiness drive cycle instead of judging success only by an extinguished MIL.
  • Check that related codes do not appear; a new companion DTC can reveal a shared-circuit or mechanical issue that was masked by the original fault.
  • Verify customer symptoms are gone under the same load, temperature and driving conditions that originally produced the complaint.

Before You Condemn

  • Confirm the exact definition of P0106 and component naming for the vehicle
  • Save freeze-frame and all related codes
  • Verify battery/charging voltage and relevant grounds
  • Inspect manifold absolute pressure (MAP)/barometric pressure rationality system connector and harness under good lighting
  • Check shared power/reference/ground circuits when multiple sensors are affected
  • Compare scan data with a known physical condition or independent measurement
  • Perform the applicable loaded circuit test, not only continuity
  • Rule out mechanical conditions that can make a good sensor report an abnormal value
  • Check for prior repairs, aftermarket modifications, oil/coolant contamination, or intake harness routing changes
  • Only replace the component after the failed circuit, response, waveform, or mechanical test is documented

Before Replacing Parts

  • Before buying a component for P0106, verify the code definition and exact component location for the vehicle, save freeze-frame, inspect the connector/harness, and perform the simplest physical checks that can make the system reading or response abnormal.
  • Compare map to baro key-on/engine-off where the design permits and then watch map response to start-up and throttle changes. If that does not prove the cause, move deliberately through circuit, scan-data and mechanical testing. Replacement is justified when the failed part can be shown to produce the wrong signal, fail a commanded response, fail an OEM bench/specification test, or remain defective after the external circuit and mechanical conditions are proven good.

Diagnostic Workflow

  1. Confirm P0106 with a capable scan tool and record whether it is current, pending, history, or intermittent. Do not clear it yet.
  2. Save freeze-frame data and all companion codes. Note engine speed, load, coolant temperature, intake temperature, throttle position, system voltage, and the PIDs directly related to Manifold Pressure / Engine Load Sensing.
  3. Check technical service information for the exact year, engine, calibration, connector pinout, monitor prerequisites, and any known software or harness issues. Do not substitute a generic pinout.
  4. Perform a focused visual inspection of manifold absolute pressure (MAP)/barometric pressure rationality system, its connector, nearby harness routing, grounds, and any hoses or passages that affect the measurement or actuator.
  5. Verify battery and charging-system voltage are stable. Low system voltage can distort actuator operation and sensor diagnostics and can create misleading secondary codes.
  6. Compare map to baro key-on/engine-off where the design permits and then watch map response to start-up and throttle changes.
  7. With key on and engine off, compare MAP to BARO or local atmospheric pressure as represented by the vehicle's available PIDs. They should be logically close on a naturally aspirated engine, subject to sensor strategy and altitude.
  8. Start the engine and observe the MAP change at idle. Determine whether the reading reflects real manifold pressure or an electrically biased signal.
  9. Inspect the MAP port, hose or manifold passage for carbon, oil, moisture, pinching or blockage. Verify the sensor is actually exposed to manifold pressure.
  10. Test reference/supply, sensor ground and signal according to the OEM circuit design. Do not assume every MAP sensor uses the same voltage range.
  11. Apply a controlled vacuum/pressure source to a removable sensor when the service procedure permits and compare scan/meter response for smoothness and repeatability.
  12. If the electrical signal is valid but pressure is implausible, check for intake vacuum leaks, EGR flow, incorrect valve timing, low compression, exhaust restriction or boost-control faults as applicable.
  13. Compare MAP response to throttle position and engine speed during a snap-throttle or controlled road test. The signal should change promptly rather than remain fixed or jump erratically.
  14. Repair the verified circuit, sensor, vacuum passage or mechanical cause. Clear the code and any learned values only when service information calls for it.
  15. Re-run the monitor and confirm P0106 remains absent while MAP/BARO/load data respond plausibly across the operating range.

Labor & Inspection Checklist

  • Verify VIN/engine and obtain the correct wiring diagram/service procedure
  • Scan all modules for related powertrain and voltage codes
  • Capture freeze-frame and baseline live data
  • Inspect access and connector condition for manifold absolute pressure (MAP)/barometric pressure rationality system
  • Check fluid level/condition or intake/vacuum integrity when relevant
  • Perform power/ground/reference and signal/driver checks
  • Perform bidirectional or functional test when supported
  • Perform mechanical verification when scan/circuit results point away from electronics
  • Document pre-repair measurements
  • Complete repair/relearn and post-repair monitor verification

Common Repairs

  • Repair confirmed wiring, connector, terminal, power, ground or reference fault
  • Replace manifold absolute pressure (MAP)/barometric pressure rationality system only when testing proves an internal failure
  • Correct the mechanical, fluid, intake, cooling or timing condition when scan data shows the sensor/actuator is reporting a real problem
  • Perform required relearn/adaptation after repair
  • Verify monitor completion and absence of pending DTCs

Common Parts

  • MAP sensor if proven
  • Vacuum hose/port components
  • Connector pigtail
  • Harness repair materials
  • Intake gasket or hose if leaking

Shop Notes

Shop note for P0106: label test results before parts replacement. Record the relevant PID graph, circuit measurements and the physical verification that proved the fault. This is especially useful if the code is intermittent or if a warranty/parts claim follows.

Before condemning manifold absolute pressure (MAP)/barometric pressure rationality system, verify the correct connector and component identification from service information. Similar-looking sensors/solenoids may share housings but use different pinouts or calibration.

If a circuit measurement is made loaded versus unloaded, document the test method. A digital multimeter can show normal voltage on an unloaded corroded circuit that fails as soon as current is demanded.

If the vehicle has multiple related codes, repair shared power, ground, reference, oil-supply, intake-leak, temperature, or mechanical-timing problems before replacing several individual components.

Gold chapter note: preserve pre-repair scan files and compare them with post-repair data. That A/B comparison is often the strongest proof that the root cause—not merely the code memory—was corrected.

Technician Notes

P0106 should be diagnosed from the monitor logic outward. The PCM is evaluating MAP signal response and plausibility relative to barometric pressure, throttle position, engine speed, calculated load and expected manifold vacuum/boost behavior. Do not let the component name in the DTC override what the failure wording says.\n\nMost efficient first move: compare MAP to BARO key-on/engine-off where the design permits and then watch MAP response to start-up and throttle changes. Keep the original freeze-frame until the fault is reproduced or the root cause is proven.\n\nUse loaded circuit testing where appropriate. Continuity alone can pass through a corroded conductor or spread terminal that cannot carry current reliably.\n\nWhen a replacement component changes the symptom but the monitor still fails, return to the root-cause model instead of installing a second part. Shared wiring, mechanical conditions, incorrect installation, relearn requirements and aftermarket modifications are common reasons for repeat failures.

Mechanic's Tip

For P0106, put the most diagnostic PIDs on one graph instead of reading them one at a time. A synchronized graph makes it easier to see whether the PCM command changes first, whether the physical system follows, and whether the feedback signal is late, biased, noisy or simply reporting a real mechanical problem.

Common Mistakes

  • Replacing manifold absolute pressure (MAP)/barometric pressure rationality system because its name appears in P0106
  • Clearing codes before saving freeze-frame and pending-code information
  • Using a universal voltage/resistance/airflow/timing number instead of vehicle-specific service data
  • Checking continuity but not voltage drop or circuit behavior under load
  • Ignoring low battery/charging voltage or shared grounds
  • Ignoring companion codes that can disable or bias the monitor
  • Failing to distinguish an electrically false reading from a mechanically real abnormal condition
  • Skipping relearn/adaptation or monitor verification after the repair

Tools Used During Diagnosis

  • Enhanced/graphing scan tool
  • Digital multimeter
  • OEM wiring diagram and service information
  • Backprobe leads/terminal test tools
  • Battery/charging-system tester
  • Hand vacuum/pressure pump when sensor design permits
  • Vacuum/pressure gauge
  • Smoke machine

Manufacturer Notes

This is a generic OBD-II code. MAF and MAP system architecture varies considerably: some vehicles use frequency-output sensors, some use voltage signals, some integrate IAT with the MAF, and some use modeled airflow as a cross-check. Use the OEM wiring diagram and PID definitions before applying voltage or grams-per-second assumptions.

Customer Explanation

Your vehicle stored P0106, which means the computer found MAP circuit range/performance or pressure plausibility error in the Manifold Pressure / Engine Load Sensing system. The code does not automatically mean manifold absolute pressure (MAP)/barometric pressure rationality system must be replaced. Wiring, connectors, operating conditions and mechanical problems can create the same code. The correct repair starts by saving the fault data, checking the simple causes, and testing the system under the conditions that caused the warning light.

Frequently Asked Questions

What does P0106 mean?

P0106 means the PCM has identified MAP circuit range/performance or pressure plausibility error involving manifold absolute pressure (MAP)/barometric pressure rationality system. It identifies the monitored fault, not automatically a failed part.

Can I drive with P0106?

Usually suitable only for limited driving when the engine runs normally and no severe warning signs are present. Diagnose promptly.

What should I check first for P0106?

Compare map to baro key-on/engine-off where the design permits and then watch map response to start-up and throttle changes. Save freeze-frame and related codes before clearing anything.

Does P0106 mean the sensor or actuator is bad?

No. Wiring, connectors, power/ground, mechanical conditions, contamination, shared circuits, calibration and the monitored component itself all have to be considered.

Will P0106 fail an emissions inspection?

Usually yes when the malfunction indicator lamp is commanded on, and clearing the code shortly before inspection can leave readiness monitors incomplete.

Can low battery voltage cause or complicate P0106?

Yes. Low cranking or charging voltage can affect sensor references, actuator response and module diagnostics. Verify electrical system health when voltage in freeze-frame is suspicious.

Should I clear P0106 before diagnosing it?

No. Record freeze-frame, pending codes and companion DTCs first. Clearing memory can erase the conditions that make the fault easier to reproduce.

When is professional equipment justified for P0106?

A bidirectional scan tool, oscilloscope, smoke machine, pressure/vacuum test equipment or OEM service information is justified when basic visual and circuit checks do not clearly prove the fault.

Can P0106 be intermittent?

Yes. Connector fretting, heat-related electronics, harness movement and marginal mechanical control can create faults that disappear in the bay. Graphing data during a road test is often more revealing than a static check.

How do I know the repair is finished?

Reproduce the original operating conditions, confirm the affected live data behaves normally, run the applicable monitor and make sure P0106 does not return as current or pending.

Related Atlas Resources

Review the related system chapter and OEM service information before specification-level testing.

Diagnostic Confidence

High after the code is reproduced and circuit/physical response is verified; Medium when the fault is intermittent and cannot be reproduced

Explore Related Atlas Resources

Related Diagnostic Codes

Related Codes

P0107 P0108 P0068 P0171 P0172

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Chapter Status

Editorial StatusAtlas Certified
Last Reviewed2026-08
Template Version2.2
Related Academy GuideUnderstanding Fuel Delivery Systems

Why Trust This Guide?

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