DTC P1440 & P1441 Confirmation Test (Overall Function Check)
NOTE:
Use the following test to check for a very small leak in EVAP system. During this test, DTC may not be confirmed.
CAUTION:
DO NOT apply more than .6 psi (4.12 kPa) of pressure to EVAP system.
- Malfunction is detected when PCM detects a very small leak in EVAP line between fuel tank and EVAP-CPVCSV. To check for a very small leak in EVAP system, connect a suitable pressure pump with gauge to EVAP service port. See Fig 1. Go to next step.
- Turn ignition on. Using scan tool, close EVAP-CVCV and open vacuum cut valve by-pass valve. Apply .79 in. Hg (2.70 kPa) of pressure to EVAP system. Monitor pressure for 60 seconds. Pressure should not drop more than .12 in. Hg (.40 kPa). If leak is greater than specified, perform DIAGNOSTIC PROCEDURE . If leak is not greater than specified, problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.