Map sensor testing

Manifold Absolute Pressure Sensor

• OPERATION
• TESTING
• REMOVAL & INSTALLATION

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OPERATION

See Figures 1, 2 and 3

Fig. Fig. 1: MAP sensor location-2.4L engine

Fig. Fig. 2: MAP sensor location-3.0L engine

Fig. Fig. 3: MAP sensor location-3.3L and 3.8L engines
The PCM supplies 5 volts of direct current to the Manifold Absolute Pressure (MAP) sensor. The MAP sensor then converts the intake manifold pressure into voltage. The PCM monitors the MAP sensor output voltage. As vacuum increases, the MAP sensor voltage decreases proportionately. Also, as vacuum decreases, the MAP sensor voltage increases proportionally.
With the ignition key ON , before the engine is started, the PCM determines atmospheric air pressure from the MAP sensor voltage. While the engine operates, the PCM figures out intake manifold pressure from the MAP sensor voltage. Based on the MAP sensor voltage and inputs from other sensors, the PCM adjusts spark advance and the air/fuel ratio. The MAP sensor is mounted to the intake manifold, near the throttle body inlet to the manifold. The sensor connects electrically to the PCM.

TESTING

See Figures 4, 5, 6 and 7

Fig. Fig. 4: Disengage the MAP sensor connector-3.0L engine shown

WARNING When testing the MAP sensor, make sure the harness wires do not become damaged by the test meter probes.

1. Visually check the connector, making sure it is attached properly and that all of the terminals are straight, tight and free of corrosion.

Fig. Fig. 5: MAP sensor connector terminal identifications: (A) 5-volt supply, (B) sensor signal, (C) ground-3.0L engine shown

Fig. Fig. 6: MAP sensor connector terminal identifications-2.4L, 3.3L and 3.8L engines

Fig. Fig. 7: Using a digital volt-ohmmeter, test the MAP sensor voltage-3.0L engine shown

1. Test the MAP sensor output voltage at the sensor connector between terminals B and C (2.4L, 3.3L and 3.8L engines), or A nd B (3.0L engine).
2. With the ignition switch ON and the engine not running, the output voltage should be 4-5 volts. The voltage should fall to 1.5-2.1 volts with a hot, neutral idle speed condition. If OK, go to the next step. If not OK, go to Step 5.
3. Test the PCM terminal 36 for the same voltage described in the previous step to make sure the wire harness is OK. Repair as necessary.
4. Test the MAP sensor ground circuit at the sensor connector terminal A (2.4L, 3.3L and 3.8L engines) or C (3.0L engine) and PCM terminal 43. If OK, go to the next step. If not OK, repair as necessary.
5. Test the MAP sensor supply voltage between the sensor connector terminals A and B (2.4L, 3.3L and 3.8L engines) r A and C (3.0L engine) with the ignition key in the ON position. The voltage should be about 4.5-5.5 volts.
6. There should also be 4.5-5.5 volts at terminal 61 of the PCM. If OK, replace the MAP sensor.
7. If not, repair or replace the wire harness as required.

REMOVAL & INSTALLATION

See Figures 1, 2, 3 and 4
The MAP sensor is mounted on the intake manifold near the throttle body inlet to the manifold.

1. Disconnect the negative battery cable.
2. On the 3.0L engine only, disconnect the vacuum hose from the MAP sensor.
3. Detach the electrical connector from the MAP sensor.
4. Unfasten the mounting screws, then remove the MAP sensor from the vehicle.

To install:

1. Install the sensor onto the intake manifold and tighten the mounting screws to 35 inch lbs. (4 Nm).
2. Attach the sensor electrical connector.
3. On the 3.0L engine, connect the vacuum hose to the MAP sensor.
4. Connect the negative battery cable.

Tge best way to test a MAP sensor is with a scanner that can read live data and a manual vacuum gauge, Connect the gauge inline with the MAP vacuum hose. Start the engine and look at the data reading for the MAP sensor. The two should agree within about 1 to 2 In./Hg. (3.3 to 6.7 kPa.)

If you find this to be incorrect, more testing should be done to determineif the problem is the MAP sensor circuits or the MAP sensor itself.

Precise testing procedures cannot be posted because yu did not mention WHICH ENGINE your Camry is equipped with or which Diagnosic Test Code (DTC) you are getting from your computer.

Hi, there are 3 different engines for the 2005 Cobalt. I have pasted instructions from Autozone.com for all 3 below. I recommend you run the test also pasted below before buying a new sensor. If your sensor passes the test, please get back to me with your symptoms and/or trouble code for alternate repair advice. Please let me know if you have any questions, and thanks for using FixYa.
Removal & Installation2.0L Engine
Supercharger Inlet Pressure (Scip) Sensor

Fig. Manifold Absolute Pressure (MAP) SCIP sensor location-2.0L engine

1. Disconnect the Supercharger Inlet Pressure (SCIP) sensor harness connector.
2. Remove the SCIP sensor (1) from the supercharger.
   WARNING: If the SCIP sensor seal is damaged, the SCIP sensor must be replaced.
   
3. Inspect the seal for damage.

To install:
NOTE: Use the new SCIP sensor seal provided with the new SCIP sensor.

1. Install the SCIP sensor (1) into the intake manifold. Tighten the bolt to 89 inch lbs. (10 Nm).
2. Connect the SCIP sensor harness connector.

Temperature Manifold Absolute Pressure (Tmap) Sensor

Fig. Manifold Absolute Pressure (MAP) TMAP sensor location-2.0L engine

1. Disconnect the Temperature Manifold Absolute Pressure (TMAP) sensor harness connector.
2. Remove the TMAP sensor from the intake manifold.
   WARNING: If the TMAP sensor seal is damaged, the TMAP sensor must be replaced.
3. Inspect the seal for damage.

To install:
NOTE: Use the new TMAP sensor seal provided with the new TMAP sensor.

1. Install the TMAP sensor into the intake manifold. Tighten the bolt to 89 inch lbs. (10 Nm).
2. Connect the TMAP sensor harness connector.

2.2L & 2.4L Engines

Fig. Manifold Absolute Pressure (MAP) sensor location-2.2L & 2.4L engines

1. Remove the throttle body.
2. Disconnect the engine harness electrical connector from the Manifold Absolute Pressure (MAP) sensor.
3. Remove the MAP sensor and seal.

To install:

1. Lubricate the NEW MAP sensor seal with clean engine oil.
2. Install the MAP sensor into the intake manifold.
3. Connect the engine harness electrical connector to the MAP sensor.
4. Install the throttle body.

Testing

1. Verify the integrity of the entire air induction system by inspecting for the following conditions:
   Any damage to, or hairline fractures of, the MAP sensor housing, Loose or improper installation, Any vacuum leak
2. Verify that restrictions do not exist in the MAP sensor port or vacuum source.
3. Determine the current vehicle testing altitude. Ignition ON, observe the scan tool BARO Sensor parameter.
4. Use the scan tool and compare the MAP Sensor parameter to a known good vehicle, under various operating conditions.

Circuit Testing

Fig. Manifold Absolute Pressure (MAP) connector end view-2.0L & 2.2L engines

Fig. Manifold Absolute Pressure (MAP) connector end view-2.4L engine

NOTE All electrical components and accessories must be turned OFF, and allowed to power down.

1. With the ignition OFF, disconnect the MAP harness connector at the MAP sensor.
2. Test for less than 5 ohms of resistance between the low reference circuit terminal 2 and ground-2.0L & 2.2L (A and ground-2.4L).
   1. If greater than the specified range, test the low reference circuit for an open/high resistance.
   2. If the circuit tests normal, replace the ECM.
3. With the ignition ON, test for 4.8-5.2 volts between the 5 volt reference circuit terminal 1 and ground-2.0L & 2.2L (C and ground-2.4L).
   1. If less than the specified range, test the 5 volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
   2. If greater than the specified range, test the 5 volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
4. Verify the scan tool MAP sensor parameter is less than 1 kPa.
   1. If greater than the specified range, test the signal circuit terminal 3-2.0L & 2.2L for a short to voltage.
   2. If the circuit tests normal, replace the ECM.
5. Install a 3A fused jumper wire between the signal circuit terminal 3-2.0L & 2.2L and the 5 volt reference circuit terminal 1-2.0L & 2.2L. Verify the scan tool MAP sensor parameter is greater than 126 kPa.
   1. If less than the specified range, test the signal circuit terminal 3-2.0L & 2.2L for a short to ground or an open/high resistance.
   2. If the circuit tests normal, replace the ECM.
6. If all circuits test normal, test or replace the MAP sensor.

Component Testing

NOTE You must perform the circuit/system testing, in order to verify the integrity of the MAP sensor circuits, before proceeding with the component testing.

1. Turn ON the ignition, with the engine OFF, and remove the MAP sensor.
2. Install a 3A fused jumper wire between the 5 volt reference circuit terminal 1-2.0L & 2.2L and the corresponding terminal of the MAP sensor.
3. Install a jumper wire between the low reference circuit terminal 2-2.0L & 2.2L of the MAP sensor and ground.
4. Install a jumper wire at terminal 3-2.0L & 2.2L of the MAP sensor.
5. Connect a DMM between the jumper wire from terminal 3 of the MAP sensor and ground.
6. Install the J 35555 to the MAP sensor vacuum port. Slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 0-5.2 volts, without any spikes or dropouts.
7. If the voltage is not within the specified range or is erratic, replace the MAP sensor.

you will need to some testing to islate problem

Turn ON the ignition, with the engine OFF.
Disconnect the MAP sensor.
Connect a voltmeter between the MAP sensor 5-volt reference circuit and a good ground.
Measure for a proper range of 4.8-5.2 volts between the MAP sensor 5-volt reference circuit and a good ground.
If the voltage is less than the specified range, then test the circuit for a high resistance. If the is normal, replace the ECM. If the voltage is more than the specified range, then test the circuit for a short to voltage. If the circuit is normal, replace the ECM.With the MAP sensor still disconnected, use the scan tool to observe the MAP Sensor parameter for the proper value of less than 12 kPa.
If the MAP Sensor parameter is more than 12 kPa, then test the MAP sensor signal circuit for a short to voltage. If the circuit is normal, replace the ECM.Connect a jumper wire between the MAP sensor 5-volt reference circuit and the MAP sensor signal circuit.
Use the scan tool to observe the MAP Sensor parameter for the proper value of more than 103 kPa.
If the MAP Sensor parameter is less than 103 kPa, then test the MAP sensor signal circuit for a high resistance. If the circuit is normal, replace the ECM.Turn OFF the ignition, and all electrical accessories. Allow sufficient time for the control module to power down before taking a resistance measurement.
Measure for a proper value of less than 5 ohms of resistance between the low reference circuit of the MAP sensor and a good ground.
If the resistance is more than 5 ohms, then test the circuit for a high resistance. If the circuit tests normal, replace the ECM.If the MAP sensor circuits test normal, then replace the MAP sensor.

Hello! One of two sensors are defective..#1....The Manifold Absolute Pressure (MAP) sensor which is bolted to the throttle body...#2 the Throttle Positioning Sensor (TPS), also bolted to the throttle body...They can be tested with a volt meter...I would need the engine size in order to send test procedures...The most likely culprit is the MAP...If you do not feel comfortable testing or you do not have a meter...Check the connector on the MAP for corroded pins and broken wires... Wire colors are...Black/White...Dark Blue/Light Green...And Orange/White...If OK, replace the MAP...Cost (3 different sensors based on engine size)...Cost is around $35 for each...


Guru...Saailer

I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

Hello! lets check the Manifold Absolute Pressure (MAP) and the Throttle Positioning Sensor (TPS) in that order...if you have a multimeter and a wee bit of experience using one both of these sensors can be tested...If not replace the MAP first and the TPS second...

The MAP has a three wire connector with wire colors Orange/White...Blue/Light Green...And Black./White...using two safety pins push one into the rear of the in-place connector into the Blue/Light Green...The other into the Black/White...connect the + probe of the meter set to read 5 volts on to the Blue/Light Green pin...the - probe to the Black/White pin...turn key to on...Meter must read at least 3 volts...If not MAP is defective...

Using the same technique lets test the TPS...Three wire connector Green/Light Green...Orange/White and Black/White...Safety pins into Green/Light Green and Blue/White...Set meter to read 5 volts...Place + probe of meter on Green/Light Green pin...And - probe on Black/White...start the engine...at idle meter must read less than 1 volt (.85)...slowly increase the idle (as best you can)...Meter should rise smoothly to 4 volts...If it skips, jumps or acts erratic the TPS is defective...See pictures below...Guru...saailer

MAP

TPS

I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

check your coolant temp sensor. possible map sensor.
The MAP sensor is fitted to the front of the throttle body except on 4.7L and 8.0L engines where it is installed on the intake manifold.

1. Remove the air cleaner assembly.
2. On throttle-body mounted MAP sensors, inspect the L-shaped tube from the throttle body to the MAP for cracks, blockage, and damage. Repair as necessary.
3. Unplug the MAP sensor connector.
4. Test the MAP sensor output voltage at the MAP sensor connector between terminals "sensor ground" and "sensor signal". With ignition ON and the engine OFF , the voltage should be between 4-5 volts.
5. Check voltage across the same terminals with the engine running at idle at operating temperature. Voltage should be 1.5-2.1 volts.
6. Test MAP sensor supply voltage at sensor connector between terminals "sensor ground" and "5v supply" with the ignition ON and engine off, voltage should be 4.5-5.0 volts.
7. Test the MAP sensor ground circuit at the "sensor ground" of the MAP connector, voltage should be less than 0.2 volts. If not inspect for open harness from pin 4 of PCM harness and terminal A . If no voltage is present, proceed to the next step.
8. Turn the ignition OFF .
9. Disconnect the PCM harness from the PCM.

WARNING Testing the wiring harness with the PCM still connected can cause serious damage to the processor. ALWAYS disconnect the PCM before testing the wiring harness, unless instructed otherwise.

1. Test the MAP sensor output voltage at the PCM connector. At the PCM cavity A-27 , the voltage should be about 5.0 volts.
2. Check the voltage at PCM cavity A-17 . It should be 5.0 volts.
3. If all of the above tests pass, plug in PCM wiring harness and MAP sensor connector.
4. With the ignition in the ON position, and the engine OFF , remove the tube from the throttle body to the MAP sensor.
5. Connect a vacuum pump to the nipple on the MAP sensor, and pump the sensor to 20-27 in. Hg. Check the sensor output voltage, it should be below 1.8 volts. If not, replace the MAP sensor. If the voltage is OK, proceed to next step.
6. Relieve vacuum pressure on the sensor, then check the output voltage. The voltage should be 4-5 volts; if not, replace the MAP sensor.
7. Install the air cleaner assembly.

the mapo sensor is bad also you could have a vacumn leak which will not let the map sensor work correctly check for air leaks and test/replace the map sensor