GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0106: Manifold Absolute Pressure (MAP) Sensor Performance

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

5-Volt Reference

P0107, P0452, P0532, P0641

P0106, P0107

P0107

P0106, P0108, P0453, P0533, P0641

P0106, P1101

Manifold Absolute Pressure Sensor Signal

P0107

P0106, P0107

P0107

P0108

P0106, P1101

Low Reference

--

P0106, P0108

P0106, P0108

--

P0106, P1101

Typical Scan Tool Data

MAP Sensor

Circuit

Short to Ground

Open or High Resistance

Short to Voltage

Operating Conditions: The ignition is ON or the engine is running

Parameter Normal Range: 12-103 kPa

5-Volt Reference

10 kPa

10 kPa

104 kPa

Manifold Absolute Pressure Sensor Signal

10 kPa

10 kPa

104 kPa

Low Reference

--

90-104¹  kPa

--

¹Variation according to the ECM version

Manifold Absolute Pressure Voltmeter

MAP Sensor

Circuit

Short to Ground

Open or High Resistance

Short to Voltage

Operating Conditions: The ignition is ON or the engine is operating

Parameter Normal Range: 4.7-5 volts

5-Volt Reference

0 V

0 V

4.98 V

Manifold Absolute Pressure Sensor Signal

0 V

0 V

4.98 V

Low Reference

--

4.5-4.98¹  V

--

¹Variation according to the ECM version

Circuit Description

The intake flow rationality diagnosis provides the within-range rationality check for the mass air flow (MAF), manifold absolute pressure (MAP), and the throttle position (TP) sensors. This is an displayed model based diagnosis containing 4 separate models for the intake system.

    • The throttle model describes the flow through the throttle body and is used to estimate the MAF through the throttle body as a function of barometric pressure (BARO), TP, intake air temperature (IAT), and estimated MAP. The information of this model is displayed on the scan tool as the MAF performance test parameter.
    • The first intake manifold model describes the intake manifold and is used to estimate MAP as a function of the MAF into the manifold from the throttle body and the MAF out of the manifold caused by engine. The flow into the manifold from the throttle uses the MAF estimate calculated from the above intake manifold model. The information of this model is displayed on the scan tool as the MAP performance test 1 parameter.
    • The only difference between the second intake manifold model and the first intake manifold model is that the second one uses MAF sensor measurement, not the throttle air flow estimated by the throttle model. The information of this model is displayed on the scan tool as the MAP performance test 2 parameter.
    • The fourth model is created from the combination and additional calculations of the throttle model and the first intake manifold model. The information of this model is displayed on the scan tool as the TP performance test parameter.

Then, the estimates of MAF and MAP calculated from this system of models and calculations are then compared with the actual measured values from the MAF, MAP, and the TP sensors and to each other to determine the appropriate DTC failing. The following table illustrates the possible failure combinations and the resulting DTC or DTCs.

MAF Performance Test

MAP Performance Test 1

MAP Performance Test 2

TP Performance Test

DTCs Passed

DTCs Failed

X

X

OK

OK

P0101, P0106, P0121, P1101

None

OK

OK

Fault

OK

P0101, P0106, P0121, P1101

None

Fault

OK

Fault

OK

P0106, P0121, P1101

P0101

OK

Fault

Fault

OK

P0101, P0121, P1101

P0106

Fault

Fault

Fault

OK

P0121, P1101

P0101, P0106

X

X

OK

Fault

P0101, P0106, P1101

P0121

OK

OK

Fault

Fault

P0101, P0106, P0121, P1101

None

Fault

OK

Fault

Fault

P0101, P0106, P0121

P1101

X

Fault

Fault

Fault

P0101, P0106, P0121

P1101

Conditions for Running the DTC

    • DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0128, P0335, P0336, P0401, P0405, P1404 are not set.
    • The engine speed is between 550-5,000 RPM.
    • The IAT sensor parameter at -7 to +60°C (+19 to +140°F).
    • The ECT sensor parameter at 70-129°C (158-264°F).
    • The DTCs run continuously when the conditions are met.

Conditions for Setting the DTC

The engine control module (ECM) detects that the MAP sensor pressure is not within range of the calculated pressure that is derived from the system of models.

Action Taken When the DTC Sets

DTC P0106 is a Type B DTC.

Conditions for Clearing the DTC

DTC P0106 is a Type B DTC.

Diagnostic Aids

    • A skewed or invariable engine coolant temperature (ECT) or IAT will cause the calculated models inaccurate and may cause the DTC to run when it should not. Refer to Temperature Versus Resistance.
    • The BARO that is used by the ECM to calculate the air flow models is initially based on the MAP sensor value at ignition ON. When the engine is running, the ECM will continually update the BARO value near wide open throttle (WOT) using the MAP sensor and a calculation. A skewed MAP sensor will cause the BARO value to be inaccurate. Use a scan tool and compare the BARO parameter with the ignition ON according to the Altitude vs. Barometric Pressure table. Refer to Altitude Versus Barometric Pressure.
    • A skewed MAP sensor value will also cause the first and second intake manifold models calculated to disagree with the actual MAP sensor measurements. Use a scan tool and compare the MAP sensor parameter with a known good vehicle parameter under various operating conditions.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Engine Control Module Scan Tool Information

Special Tools

J 35555 Metal Mityvac

Circuit/System Verification

  1. If DTC P0107, P0108, P0641 or P0651 is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  2. Turn the ignition ON, observe the scan tool MAP sensor parameters. Verify the MAP sensor parameter reading is within the current BARO for your altitude. Refer to Altitude Versus Barometric Pressure.
  3. Turn the ignition ON, review the MAP sensor kPa parameter with a scan tool. Start the engine. The MAP sensor kPa parameter should decrease.
  4. Verify the integrity of the air induction system by inspecting for the following conditions:
  5. • Damaged components
    • Loose or improper installation
    • Restricted air flow
    • A cracked or restricted MAP sensor vacuum hose
    • Intake manifold leak
  6. Turn the ignition ON, compare APP sensors 1 and 2 percentages with a scan tool. Lightly depress the pedal, verify that their difference is not more than 5 percent.

Circuit/System Testing

Note:  You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Turn the ignition OFF, allow sufficient time for the control module to power down. Disconnect the harness connector at the MAP sensor.
  2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal A and ground.
  3. If greater than the specified range, test the low reference circuit for an open or high resistance. If the circuit test normal, replace the ECM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground, open, or high resistance. If the circuit tests normal, replace the ECM.
    If greater than the specified range, test the 5-volt reference circuit for short to voltage. If the circuit test normal, replace the ECM.
  6. Verify the scan tool MAP sensor parameter is less than 0.2 volt.
  7. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit test normal, replace the ECM.
  8. Connect a 3-amp fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool MAP sensor parameter is more than 4.9 volts.
  9. If less than the specified range, test the signal circuit for a short to ground, or an open or high resistance. If the circuit tests normal, replace the ECM.
  10. If all circuits test normal, test or replace the MAP sensor.

Component Testing

Note:  You must perform the Circuit/System Testing before proceeding with Component Testing.

  1. Turn the ignition OFF, remove the MAP sensor.
  2. Install a 3-amp fused jumper wire between the 5-volt reference circuit terminal C of the sensor and 5 volts.
  3. Install a jumper wire between the low reference circuit terminal A of the sensor and ground.
  4. Install the J 35555 to the MAP sensor vacuum fitting. Slowly draw vacuum to the sensor while monitoring the voltage between the signal terminal B and the low reference terminal A. The voltage should vary between 0.2-4.9 volts and should not beyond this range.
  5. If the voltage is not within the specified range or is unstable, replace the MAP sensor.

Repair Instructions

    •  Manifold Absolute Pressure Sensor Replacement
    •  Control Module References for ECM replacement, setup, and programming

Repair Verification

  1. Turn the ignition ON, observe the MAP sensor parameter with a scan tool. Verify the MAP sensor parameter reading is within the current BARO for your altitude. Refer to Altitude Versus Barometric Pressure.
  2. Turn the ignition ON, review the MAP sensor kPa parameter with a scan tool. Start the engine. The MAP sensor kPa parameter should decrease.