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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Grand Am 🢒 Engine 🢒 Engine Controls - 2.2L (L61) 🢒 DTC P0106

Circuit Description

The powertrain control module (PCM) supplies a 5-volt reference circuit and a low reference circuit to both the throttle position (TP) sensor and the manifold absolute pressure (MAP) sensor. The TP sensor sends a voltage signal back to the PCM relative to the throttle plate opening, and the MAP sensor sends a voltage signal back to the PCM relative to the intake manifold pressure. The PCM can detect if the TP sensor or the MAP sensor are out of range by comparing the two values against the high and low limits and engine speed defined within the engine calibration. If the TP or the MAP are not within the expected limits of the engine calibration, DTC P0106 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0106 Manifold Absolute Pressure (MAP) Sensor Performance

Conditions for Running the DTC
    • DTCs P0107, P0108, P0117, P0118, P0122, P0123, P0125, P0128, P0131, P0132, P0171, P0172, P0201, P0202, P0203, P0204, P0300, P0336, P0340, P0341, P0442, P0446, P0452, P0453, P0455, P0496, P0502, P0506, P0507, P0601, P0602, P1621, P1860 are not set.
    • The engine speed is between 600-6,375 RPM.
    • The change in engine speed is less than 50 RPM.
    • The engine run time is more than 40 seconds.
    • The torque converter clutch (TCC) is stable to within 1.2 percent, if equipped.
    • The idle air control (IAC) valve is stable to within 5 counts.
    • The above conditions are met for 1.5 seconds.
    • This DTC runs continuously within the enabling conditions.

Conditions for Setting the DTC

The MAP sensor or the TP sensor is out of an expected range defined by the engine calibration for 14 seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
    • If a DTC P0106 cannot be duplicated, the information included in the Freeze Frame/Failure Records data can be used in locating an intermittent condition.
    • A TP sensor that is stuck may attempt to auto zero every time the engine runs. An indication if this happens is the TP percentage will be 0 percent and TP voltage will be high.
    • This DTC may set as the result of a misfire.
    • If the condition is intermittent, refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests the ability of the MAP sensor to respond to a pressure change.

    2.

  2. The measurement noted in this step will be used in subsequent steps if the measurement is not more than the specified value.

    3.

  3. This step calculates the resistance in the 5-volt reference circuit of the MAP sensor.

    4.

  4. This step calculates the resistance in the low reference circuit of the MAP sensor.

    5.

  5. The measurement noted in this step will be used in subsequent steps if the measurement does not exceed the specified value.

    6.

  6. This step calculates the resistance in the 5-volt reference circuit of the TP sensor.

    7.

  7. This step calculates the resistance in the low reference circuit of the TP sensor.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Inspect for the following conditions:

    • Any disconnected, damaged, or incorrectly routed vacuum hoses
    • The manifold absolute pressure (MAP) sensor disconnected from vacuum source
    • Any restrictions in the MAP sensor vacuum source
    • Any intake manifold vacuum leaks

Did you find and correct the condition?

--

Go to Step 44

Go to Step 3

3
  1. Turn ON the ignition, with the engine OFF.
  2. Observe the throttle position (TP) sensor voltage with a scan tool.

Is the voltage less than the specified value when the throttle is fully closed?

0.85 V

Go to Step 4

Go to Step 5

4

  1. Observe the TP sensor angle with a scan tool.
  2. Monitor the scan tool while slowly depressing the accelerator pedal to the floor, then slowly release the pedal. Repeat the procedure several times.

Does the TP angle increase steadily when the accelerator pedal is depressed to more than the first specified value and decrease steadily, returning to less than the second specified value when the pedal is released?

98%

1%

Go to Step 6

Go to Step 21

5

Inspect the throttle body for the following conditions:

    • A binding or damaged throttle cable
    • A damaged throttle blade
    • A binding or damaged cruise control cable

Did you find and correct the condition?

--

Go to Step 44

Go to Step 21

6

Important: The vehicle used for the comparison is not limited to the same type of vehicle as is being serviced. A vehicle known to provide an accurate reading is acceptable.

Do you have access to another vehicle in which the MAP sensor pressure can be observed with a scan tool?

--

Go to Step 7

Go to Step 8

7
  1. Turn ON the ignition, with the engine OFF.
  2. Observe the MAP sensor pressure with a scan tool.
  3. Observe the MAP sensor pressure in the known good vehicle with a scan tool.
  4. Compare the values.

Is the difference between the values less than the specified value?

3 kPa

Go to Step 9

Go to Step 14

8

Important: The Altitude vs Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range.

  1. Turn ON the ignition, with the engine OFF.
  2. Observe the MAP sensor pressure with a scan tool. Refer to Altitude Versus Barometric Pressure .
  3. The MAP sensor pressure should be within the range specified for your altitude.

Does the MAP sensor indicate the correct barometric pressure?

--

Go to Step 9

Go to Step 14

9

  1. Remove the MAP sensor from the engine vacuum source. Leave the MAP sensor connected to the engine harness.
  2. Connect a J 23738-A Mityvac to the MAP sensor.
  3. Observe the MAP sensor pressure with a scan tool.
  4. Apply vacuum with the J 23738-A until 5 inch Hg is reached.

Does the MAP sensor pressure change?

--

Go to Step 10

Go to Step 14

10
  1. Observe the MAP sensor pressure with the scan tool.
  2. Apply vacuum with the J 23738-A in 1 inch Hg increments until 15 inch Hg is reached. Each 1 inch Hg should decrease the MAP sensor pressure by 3-4 kPa.

Is the decrease in MAP sensor pressure consistent?

--

Go to Step 11

Go to Step 14

11

Apply vacuum with the J 23738-A until 20 inch Hg is reached.

Is the MAP sensor pressure less than the specified value?

34 kPa

Go to Step 12

Go to Step 14

12

Disconnect the J 23738-A from the MAP sensor.

Does the MAP sensor pressure return to the value observed in Step 7 or Step 8?

--

Go to Step 13

Go to Step 41

13

Test for the following conditions:

    • Restricted exhaust--Refer to Restricted Exhaust in Engine Exhaust.
    • Worn piston rings--Refer to Engine Compression Test in Engine Mechanical.
    • Incorrect cam timing--Refer to Camshaft Timing Chain, Sprocket, and Tensioner Replacement in Engine Mechanical for the correct timing.

Did you find and correct the condition?

--

Go to Step 44

Go to Diagnostic Aids

14
  1. Turn OFF the ignition.
  2. Disconnect the MAP sensor electrical connector.
  3. Turn ON the ignition.
  4. Observe the MAP sensor voltage with a scan tool.

Is the voltage less than the specified value?

0.2 V

Go to Step 15

Go to Step 28

15

Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DMM. Note the measurement as "Supply voltage".

Is the voltage more than the specified value?

5.2 V

Go to Step 26

Go to Step 16

16

Is the voltage more than the specified value?

4.8 V

Go to Step 17

Go to Step 27

17
  1. Connect a test lamp and a DMM in series between the 5-volt reference circuit and the low reference circuit of the MAP sensor at the harness connector.
  2. Measure the amperage with the DMM. Note the measurement as "Amperage" .

Is the amperage equal to the specified value?

0 mA

Go to Step 30

Go to Step 18

18

  1. Remove the DMM from the circuit.
  2. Connect the test lamp between the 5-volt reference circuit and the low reference circuit of the MAP sensor at the harness connector.
  3. Measure the voltage from the 5-volt reference circuit at the test lamp to a good ground with the DMM. Note the measurement as "Load voltage drop".

    4. Important: Before any calculations are performed, ensure that all measurements are converted to like units. For example, volts/amps or millivolts/milliamps.

  4. Subtract the "Load voltage drop" from the "Supply voltage". Note the result as "Supply voltage drop".
  5. Divide the "Supply voltage drop" by the "Amperage".

Is the result more than the specified value?

5 ohms

Go to Step 29

Go to Step 19

19

  1. Measure the voltage from the low reference circuit of the MAP sensor at the test lamp to a good ground with the DMM. Note the result as "Low reference voltage drop".

    2. Important: Before any calculations are performed, ensure that all measurements are converted to like units. For example, volts/amps or millivolts/milliamps.

  2. Divide the "Low reference voltage drop" by the "Amperage".

Is the result more than the specified value?

5 ohms

Go to Step 31

Go to Step 20

20
  1. Remove the test lamp.
  2. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the MAP sensor and the signal circuit of the MAP sensor.
  3. Observe the MAP Sensor parameter with the scan tool.

Is the voltage more than the specified value?

4.9 V

Go to Step 37

Go to Step 32

21

  1. Remove the air cleaner outlet resonator. Refer to Air Cleaner Outlet Resonator Replacement .
  2. Disconnect the TP sensor.
  3. Measure the voltage from the 5-volt reference circuit of the TP sensor to a good ground with a DMM. Note the measurement as "Supply voltage".

Is the voltage more than the specified value?

5.2 V

Go to Step 33

Go to Step 22

22

Is the voltage more than the specified value?

4.8 V

Go to Step 23

Go to Step 25

23

  1. Connect a test lamp and a DMM in series between the 5-volt reference circuit and the low reference circuit of the TP sensor at the harness connector.
  2. Measure the amperage with the DMM. Note the measurement as "Amperage".
  3. Remove the DMM from the circuit.
  4. Connect the test lamp between the 5-volt reference circuit and the low reference circuit of the TP sensor at the harness connector.
  5. Measure the voltage from the 5-volt reference circuit at the test lamp to a good ground with the DMM. Note the measurement as "Load voltage drop".

    6. Important: Before any calculations are performed, ensure that all measurements are converted to like units. For example, volts/amps or millivolts/milliamps.

  6. Subtract the "Load voltage drop" from the "Supply voltage". Note the result as "Supply voltage drop".
  7. Divide the "Supply voltage drop" by the "Amperage".

Is the result more than the specified value?

5 ohms

Go to Step 34

Go to Step 24

24

  1. Measure the voltage from the low reference circuit of the TP sensor at the test lamp to a good ground with the DMM. Note the result as "Low reference voltage drop".

    2. Important: Before any calculations are performed, ensure that all measurements are converted to like units. For example, volts/amps or millivolts/milliamps.

  2. Divide the "Low reference voltage drop" by the "Amperage".

Is the result more than the specified value?

5 ohms

Go to Step 35

Go to Step 38

25
  1. Leave the DMM connected.
  2. Disconnect the air conditioning (A/C) refrigerant pressure sensor and the fuel tank pressure (FTP) sensor, one at a time.
  3. Observe the DMM each time a sensor is disconnected.

Does the voltage measure more than the specified value after either of the sensors are disconnected?

4.8 V

Go to Step 40

Go to Step 36

26

Test the 5-volt reference circuit of the MAP sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 43

27

Test the 5-volt reference circuit of the MAP sensor for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

28

Test the MAP sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 43

29

Test the 5-volt reference circuit of the MAP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

30

Test the MAP sensor low reference circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

31

Test the MAP sensor low reference circuit for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

32

Test the MAP sensor signal circuit for the following conditions:

    • An open
    • A short to ground
    • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

33

Test the 5-volt reference circuits of the following sensors for a short to voltage:

    • The TP sensor
    • The A/C refrigerant pressure sensor
    • The FTP sensor

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 43

34

Test all of the 5-volt reference circuit of the TP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

35

Test the low reference circuit of the TP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 39

36

Test the 5-volt reference circuits of the following sensors for a short to ground:

    • The TP sensor
    • The A/C refrigerant pressure sensor
    • The FTP sensor

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 43

37

Test for poor connections at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 41

38

Test for poor connections at the TP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 42

39

Test for poor connections at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 44

Go to Step 43

40

Replace the component for which the voltage changed. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement in Heating, Ventilation, and Air Conditioning or Fuel Tank Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 44

--

41

Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 44

--

42

Replace the TP sensor. Refer to Throttle Position Sensor Replacement .

Did you complete the replacement?

--

Go to Step 44

--

43

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 44

--

44
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 45

45

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK