Voltage Readings on M.a.p Sensor for 2013 Chevy Cruze

Typically found in fuel injected engines, the manifold absolute pressure (MAP) sensor is i of the sensors an engine control module (ECM) uses to calculate fuel injection for optimal air-fuel ratio by continuously monitoring intake manifold pressure information. More commonly a mass airflow (MAF) sensor is used in place of a MAP sensor, however, turbocharged engines volition typically use both a MAP and a MAF sensor.  The MAP sensor besides provides a vital part in helping the ECM determine when the ignition should occur nether varying engine load conditions.

Whichever sensor your engine uses, the ECM will not exist able to optimize fuel injection without accurate air mass information from a working sensor. And poor air-fuel ratio at the very least will cause performance issues and premature engine vesture. A MAP sensor failure tin be difficult to diagnose, but with the aid from Delphi Technologies, we can explicate what causes it, what to look out for, and how to replace it if information technology fails.

How does a MAP sensor work?

The MAP sensor is typically located on the intake manifold, either next to or on the throttle body itself. (On a forced-induction engine, the MAP sensor tin be found on the intake tract before the turbo.) Inside the MAP sensor is a sealed chamber that either has a vacuum or a controlled force per unit area that is calibrated for the engine. Dividing the sensor vacuum and the vacuum from the intake manifold is a flexible silicon wafer (a.k.a. 'chip') with a electric current running through it.

The MAP sensor performs 'double duty' as a barometric pressure sensor as before long every bit the cardinal is turned on.  With the cardinal turned on (prior to the engine starting) there is no vacuum in the engine applied to the MAP sensor therefore it's signal to the ECM becomes a baro reading helpful in determining air density.  When you outset the engine, pressure in the intake manifold decreases creating a vacuum that is applied to the MAP sensor.  When you press on the gas accelerator pedal, the pressure level in the intake manifold increases, resulting in less vacuum. The differences in pressure will flex the bit up into the sealed chamber, causing a resistance modify to the voltage, which in turn tells the ECU to inject more fuel into the engine. When the accelerator pedal is released, the pressure level in the intake manifold decreases, flexing the clip dorsum to its idle country.

The ECU combines the manifold pressure readings from the MAP sensor with data coming from the IAT (intake air temperature), ECT (Engine Coolant Temperature) sensor, baro reading and engine speed (RPM) to summate air density and accurately determine the engine's air mass flow charge per unit for optimal air-fuel ratio.

Why do MAP sensors neglect?

Like almost electrical sensors, MAP sensors are sensitive to contamination. If the map sensor uses a hose, the hose tin become clogged or leak and unable to read pressure changes. In some cases, extreme vibrations from driving can loosen its connections and cause external damage. Electrical connectors can also cook or crack from overheating due to shut proximity to the engine. In either of these scenarios, the MAP sensor will demand to be replaced.

What to wait out for in a failing MAP sensor

A faulty MAP sensor will impact an engine'southward air-fuel ratio. If the ratio is incorrect, ignition inside the engine will occur at an improper time in the combustion bicycle. If severe pre-detonation continues over an extended fourth dimension, the internal parts of the engine (such every bit pistons, rods, rod bearings) will become damaged and eventually pb to catastrophic failure. Look for these alarm signs:

• Rich air-fuel ratio: Look for crude idle, poor fuel economic system, slow acceleration and a strong smell of gasoline (specially at idle)
• Lean air-fuel ratio: Expect for surging, stalling, lack of power, hesitation on acceleration, backfiring through the intake, and overheating
• Detonation and misfire
• Failed emissions test
• Check engine light

A rebuilt engine is much more of a hassle than replacing a sensor, so if your engine is experiencing whatever of the symptoms above, consider troubleshooting your MAP sensor.

Common MAP sensor fault codes

Here is a listing of codes that are associated with the MAP sensor to look for if your check engine light has turned on:

• P0068: MAP/MAF - Throttle Position Correlation
• P0069: Manifold Absolute Pressure - Barometric Pressure level Correlation
• P0105: MAP Excursion Malfunction
• P0106: MAP/Barometric Pressure Circuit Range/Functioning Problem
• P0107: Manifold Absolute Pressure/Barometric Pressure Excursion Low Input
• P0108: MAP Pressure Excursion High Input
• P0109: MAP / Baro Pressure Circuit Intermittent
• P1106: MAP/BARO Pressure Circuit Range/Functioning Problem
• P1107: Barometric Pressure Sensor Circuit Low Voltage

Annotation: Sometimes different sensors or other faulty parts tin can cause these codes to set. Even if your engine is experiencing the symptoms listed above and is firing one or more of the OBD-2 codes listed, it is recommended to test the MAP sensor to confirm information technology is faulty.

How to troubleshoot a MAP sensor

Before whatever tests, audit the physical appearance of the MAP sensor. Brainstorm past checking the connector and wiring for any damage, such every bit melted or cracked wires, and confirm there are no loose connections. Disconnect the sensor and inspect the pins; they should be straight and clean with no signs of corrosion or bending. Adjacent, inspect the hose (if applicable) connecting the sensor to the intake manifold for any signs of damage and that it has a tight connection to the sensor. Lastly, take a look inside the hose to make sure information technology is costless of contamination.

If everything passes physical inspection, yous can test the MAP sensor using a digital multimeter ready to 20V and a vacuum pump.

1. With the battery on and engine off, connect the multimeter basis to the negative battery concluding and run a quick plausibility by checking the voltage of the battery. It should be around 12.6 volts.
2. Consult the manufacturer's service manual to identify the signal, basis, and 5-volt reference and back-probe the wires.
3. Plow the ignition switch on without starting the engine. The multimeter should (typically) display a voltage betwixt iv.5 to five volts for the 5-volt reference, a steady 0 volts for the ground wire, and between 0.five and 1.v volts for the signal wire on not turbo applications and between 2.0 and 3.0 for turbo applications. Consult OEM factory service information for the exact specs on your vehicle.
4. Start the engine with the signal wire dorsum-probed. The multimeter should brandish a voltage between .five to i.five volts at sea level on non turbo charged vehicles and 2.0 to 2.5 volts on turbocharged models.
5. Turn the engine off just keep the ignition on.
6. Under the hood, disconnect the MAP sensor from the intake just.
7. Connect a hand vacuum pump and notation the current voltage from the point wire.
8. Increase the vacuum on the sensor using the vacuum pump.
9. The voltage should steadily drib as the vacuum increases.

If your voltage differs greatly on either examination or the voltage alter is erratic, the MAP sensor is faulty and will need to be replaced.

How to replace a faulty MAP sensor

Replacing a bad MAP sensor varies by vehicle, so please consult the manufacturer's service manual for instructions for any specific instructions. Once the faulty sensor has been removed, information technology's a straight forrard installation for the new function.

1. Locate the MAP sensor on the intake manifold, either adjacent to or on the throttle trunk itself, or on the intake manifold.
2. Remove any screws or bolts property the sensor in place.
3. Disconnect the electrical connector. Note: Do not force removal equally the connector may incorporate a locking tab that may demand to exist removed prior to unlatching the connector from the sensor.
4. If applicable, detach the vacuum hose from the sensor. Notation: It is recommended to supervene upon the vacuum hose with a new hose when replacing the sensor.
5. Compare the new and old sensors.
6. If applicable, reconnect the vacuum hose.
7. Reconnect the sensor electrical connector.
8. Reinstall whatsoever screws or bolts that hold the sensor in place.
9. Double-cheque all connections to make sure everything is secured.

Note: Depending on the vehicle and if a trouble code was set, a diagnostic tool may be required to reset the cheque engine light.

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Source: https://www.delphiautoparts.com/gbr/en/resource-center/making-sense-your-sensors-map-sensor

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