For 1990-2009 cars

### 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 Descriptors

DTC P0106 00: Manifold Absolute Pressure (MAP) Sensor Performance
DTC P0107 00: Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage
DTC P0108 00: Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to voltage | Signal Performance
--- | --- | --- | --- | --- | ---
5 V Reference | P0107 00 | P0106 00, P0107 00 | P0107 00 | P0108 00 | P0106 00, P0107 00
MAP Sensor Signal | P0107 00 | P0106 00, P0107 00 | P0107 00 | P0106 00, P0108 00 | P0106 00, P0107 00
Low Reference | -- | P0106 00, P0107 00 | P0106 00, P0108 00 | -- | P0106 00, P0108 00

### Typical Scan Tool Data

#### MAP Sensor

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Engine running, transmission in Park or Neutral Parameter Normal Range: 20-48 kPa (2.9-7 PSI) (varies with altitude)
5 V Reference | 0 kPa, (0 PSI) | 0 kPa, (0 PSI) | 127 kPa (18.4 PSI)
MAP Sensor Signal | 0 kPa, (0 PSI) | 0 kPa, (0 PSI) | 127 kPa (18.4 PSI)
Low Reference | -- | 127 kPa (18.4 PSI) | --

### Circuit/System Description

The MAP sensor has a 5 V reference circuit, a low reference circuit, and a signal circuit. The engine control module (ECM) supplies 5 V to the MAP sensor on a 5 V reference circuit, and provides a ground on a low reference circuit. The MAP sensor provides a voltage signal to the ECM on a signal circuit relative to the intake manifold pressure changes.

### Conditions for Running the DTC

#### P0106 00

• | DTCs P0107 00, P0108 00, P0111 00, P0112 00, P0113 00, P0114 00, P0116 00, P0117 00, P0118 00, P0119 00, P0128 00, P0335 00, P0336 00 are not set

• | The engine is running greater than or equal to 400 RPM.

• | The IAT Sensor parameter is between -7 to +125°C (19 to 257°F).

• | The ECT Sensor parameter is between 70-125°C (158-257°F).

• | This DTC runs continuously when the above conditions are met.

#### P0107 00

• | DTCs P0120 00, P0121 00, P0122 00, P0123 00, P0220 00, P0221 00, P0222 00, P0223 00 or P0641 00 are not set

• | The engine is running greater than or equal to 400 RPM.

• | The throttle position is greater than or equal to 0% when the engine speed is less than or equal to 1000 RPM

- OR

• | The throttle position is greater than or equal to 12.5% when the engine speed is greater than 1000 RPM.

• | The DTC runs continuously when the above conditions are met.

#### P0108 00

• | The engine has been running for a length of time that is determined by the start-up coolant temperature. The length of time ranges from 5.5 min at colder than -30°C (-22°F) to 10 s at greater than 30°C (+86°F).

• | DTCs P0120 00, P0121 00, P0122 00, P0123 00, P0220 00, P0221 00, P0222 00, P0223 00 or P0641 00 are not set

• | The throttle position is less than or equal to 1% when the engine speed is less than or equal to 1200 RPM.

- OR

• | The throttle position is less than or equal to 20% when the engine speed is greater than 1200 RPM.

• | The DTC runs continuously when the above conditions are met.

### Conditions for Setting the DTC

#### P0106 00

The ECM detects that the MAP Sensor pressure is not within range of the calculated pressure that is derived from the system of models for more than 0.5 s.

#### P0107 00

The ECM detects that the MAP sensor voltage is less than 0.05 V for greater than 5 s.

#### P0108 00

The ECM detects that the MAP sensor voltage is more than 4.9 V for greater than 5 s.

### Action Taken When the DTC Sets

DTCs P0106 00, P0107 00 and P0108 00 are Type B DTCs.

### Conditions for Clearing the DTC

DTCs P0106 00, P0107 00 and P0108 00 are Type B DTCs.

### Diagnostic Aids

#### P0106 00

Note: Verify that the engine is in good mechanical condition before continuing with this diagnostic.

• | A skewed or stuck ECT sensor or IAT sensor will cause the calculated models to be inaccurate and may cause this 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 at ignition ON. When the engine is running, the ECM will continually update the BARO value near wide open throttle using the MAP sensor and a calculation. A skewed MAP sensor will cause the BARO value to be inaccurate. Use the scan tool and compare the BARO parameter at ignition ON to the Altitude vs. Barometric Pressure Table. Refer to Altitude Versus Barometric Pressure.

• | A skewed MAP sensor will also cause the first and second intake manifold models to disagree with the actual MAP sensor measurements. Use the scan tool and compare the MAP Sensor parameter to a known good vehicle, under various operating conditions.

• | Inspect for the following conditions:

• | Incorrect camshaft timing--Refer to LINK (Timing Belt Adjustment) for the correct timing.

• | Worn piston rings--Refer to Engine Compression Test.

### 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

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

#### Special Tools

EN-23738-A Mityvac

For equivalent regional tools, refer to Special Tools.

### Circuit/System Verification

1. Verify that the following DTCs are not set: P0642 00, P0643 00, P0652 00, or P0653 00.

⇒ | If any of the DTCs are set, refer to LINK DTC P0642 00, P0643 00, P0652 00, or P0653 00.

2. Ignition ON, observe the scan tool MAP Sensor parameter. The reading should be between 0.05-4.9 V.

⇒ | If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

3. 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 data.

### Circuit/System Testing

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

1. Ignition OFF, disconnect the harness connector at the B74 Manifold Absolute Pressure (MAP) Sensor.
2. Ignition OFF for 90 s, test for less than 5 Ω between the low reference circuit terminal 2 and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground.

⇒ | If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

⇒ | If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

4. Verify the scan tool MAP Sensor parameter is less than 2 kPa (0.3 PSI).

⇒ | If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 1. Verify the scan tool MAP Sensor parameter is greater than 126 kPa (18 PSI).

⇒ | If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

6. If all circuits test normal, test or replace the B74 Manifold Absolute Pressure (MAP) Sensor.

### Component Testing

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

#### Dynamic Test

1. Ignition OFF, remove the B74 Manifold Absolute Pressure (MAP) Sensor.
2. Install a 3 A fused jumper wire between the 5 V reference circuit terminal 1 and the corresponding terminal of the B74 Manifold Absolute Pressure (MAP) Sensor.
3. Install a jumper wire between the low reference circuit terminal 2 of the B74 Manifold Absolute Pressure (MAP) Sensor and ground.
4. Install a jumper wire at terminal 3 of the B74 Manifold Absolute Pressure (MAP) Sensor.

⇒ | If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the ECM.

5. Connect a DMM between the jumper wire from terminal 3 of the B74 Manifold Absolute Pressure (MAP) Sensor and ground.
6. Ignition ON, with the EN-23738-A Mityvac slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 0-5.2 V, without any spikes or dropouts.

⇒ | If the voltage reading is erratic, replace the B74 Manifold Absolute Pressure (MAP) Sensor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Manifold Absolute Pressure Sensor Replacement

• | Engine Control Module Replacement for ECM replacement, setup, and programming