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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2004 🢒 DeVille 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Inspection/Maintenance (I/M) Complete System Set Procedure

Description

The purpose of the I/M Complete System Set Procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics, and complete the trips for those particular diagnostics. When all diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform this test when more than one of the I/M System Status indicators are set to NO.

Conditions for Running
    • The barometric pressure (BARO) is more than 72 kPa.
    • The engine coolant temperature (ECT) is between 5-120°C (41-248°F).
    • The intake air temperature (IAT) is between -6 to +200°C (+21 to +392°F).
    • The battery voltage is between 9-18 volts.
    • The fuel level is between ¼ and ¾.

Test Description

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

  1. This step runs the HO2S Heater Tests and initiate the evaporative emission (EVAP) System Test.

    Preprogramming the scan tool will reduce the amount of time the oxygen sensor heaters operate while verifying the enable criteria.

    2.

  2. This step runs the EVAP, secondary air injection (AIR) and the oxygen sensor (O2S) tests. The EVAP test begins once the engine coolant reaches a calibrated temperature. The AIR test, if equipped, begins shortly after Closed Loop and the indicated speed is achieved. The oxygen sensor tests begin once the engine is at operating temperature, in Closed Loop fuel control, and a calibrated amount of time has elapsed.

    3.

  3. This step runs the exhaust gas recirculation (EGR) tests. The EGR tests are run during a gradual deceleration with a closed throttle. The vehicle speed is required in order to maintain a high, steady manifold absolute pressure (MAP) signal.

    4.

  4. This step runs the catalyst tests. This test runs during the idle period immediately following a cruise period that meets a minimum calibrated RPM and time period.

Step

Action

Value(s)

Yes

No

1

Did you perform the Inspection/Maintenance (I/M) System Check?

--

Go to Step 2

Go to Inspection/Maintenance (I/M) System Check

2

    Important: Whenever the ignition is turned ON, ignition positive voltage is supplied to the heated oxygen sensor (HO2S) heaters. After verifying the enable criteria, turn OFF the ignition for approximately 5 minutes to allow the sensors to cool before continuing with the test. Once the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure.

  1. Preprogram the scan tool with the vehicle information before the ignition is turned ON.
  2. Ensure that the vehicle is within the Conditions for Running, as specified in the supporting text.
  3. Turn OFF all of the accessories, e.g., A/C, blower fan, etc.
  4. Set the vehicle parking brake.
  5. Verify the transmission is in Park for automatic transmissions and Neutral for manual transmissions.
  6. Start the engine and allow the engine to idle for the specified time.

Is the action complete?

2 minutes

Go to Step 3

--

3

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Acceleration at part throttle to 90 km/h (55 mph) with this speed maintained until the engine reaches operating temperature. This may be up to 10 minutes depending on the start up coolant temperature.
  2. Continued operation under these conditions for an additional 6 minutes.

Is the action complete?

--

Go to Step 4

--

4

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Vehicle speed reduced to 72 km/h (45 mph) with this speed maintained for one additional minute.
  2. Four decelerations of 25 seconds each from 72 km/h (45 mph) while the following criteria is maintained:
    3. • Throttle is closed
    • NO brake application on either manual or automatic transmission
    • NO clutch actuation on a manual transmission
    • NO manual downshift
    • Vehicle speed remains above 40 km/h (25 mph)
    • After each deceleration period, vehicle is returned to 72 km/h (45 mph) under part throttle acceleration and speed is maintained for 15 seconds.

Is the action complete?

--

Go to Step 5

--

5

Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

In order for the next group of tests to run, the vehicle must operate in the following conditions:

  1. Acceleration at part throttle to 75-89 km/h (45-55 mph) with this speed maintained for 2 minutes.
  2. Deceleration to 0 km/h (0 mph).
  3. Engine idling for 2 minutes while the following criteria is maintained:
    4. • Service brake pressed
    • Automatic transmission in drive
    • Manual transmission in neutral with the clutch pedal pressed

Is the action complete?

--

Go to Step 6

--

6

Observe the I/M System Status display with a scan tool.

Did all of the I/M System Status indicators update to YES?

--

Go to Step 7

Go to the I/M System Set Procedure for the indicated systems that have not updated

7

Observe the Emission Related DTC portion of the I/M System Status display with a scan tool.

Does the scan tool indicate any Emission Related DTCs set?

--

Go to Inspection/Maintenance (I/M) System DTC Table

System OK