Description
This DTC tests for undesired intake manifold vacuum flow to the EVAP system. The control module seals the EVAP system by commanding the EVAP purge valve OFF (closed) and the EVAP vent valve ON (closed). The control module monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time DTC P1441 will set.
Conditions for Running the DTC
| • | DTC P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0125, P0443, P0449, P0452, P0453, P1106, P1107, P1112, P1114, P1115, P1120, P1220, or P1221 are not set. |
| • | The ignition voltage is between 10-18 volts. |
| • | The barometric pressure is more than 75 kPa. |
| • | The fuel level is between 15-85 percent. |
| • | The engine coolant temperature (ECT) is between 4-30°C (39-86°F). |
| • | The intake air temperature (IAT) is between 4-30°C (39-86°F). |
| • | The start up ECT and IAT are within 9°C (16°F) of each other. |
| • | The vehicle speed sensor (VSS) is less than 121 km/h (75 mph). |
Conditions for Setting the DTC
The control module detects vacuum during a non purge condition.
Action Taken When the DTC Sets
| • | The control module will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test ran and failed. |
| • | The control module will store conditions which were present when the DTC set as Freeze Frame and Failure Records data. |
Conditions for Clearing the MIL/DTC
| • | The control module will turn OFF the MIL during the third consecutive trip in which the diagnostic ran and passed. |
| • | The History DTC will clear after 40 consecutive warm-up cycles without a malfunction. |
| • | The DTC can be cleared with a scan tool. |
Diagnostic Aids
An intermittent condition could be caused by an improperly installed or damaged EVAP canister purge valve or by a temporary blockage in the EVAP canister purge valve. In order to repair a blockage in the EVAP system, refer to Evaporative Emission System Cleaning .
Test Description
The number below refer to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Evaporative Emissions Hose Routing Diagram | ||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |
2 | Are DTCs P0443, P0449, P0452, or P0453 also set? | -- | Go to Step 3 | |
3 |
Does the scan tool indicate fuel tank pressure within the specified range? | -0.5 to +0.5 in H2O | Go to Step 4 | Go to DTC P0453 |
4 |
Does the vacuum gauge indicate an increase in vacuum? | -- | Go to Step 5 | Go to Diagnostic Aids |
5 | Replace the EVAP canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement . Did you complete the replacement? | -- | Go to Step 6 | -- |
Does the scan tool indicate that the Service Bay Test has passed? | -- | Go to Step 7 | Go to Step 3 | |
7 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |
