Cold start: with ambient temperature (obtained from modeling the inlet air temperature sensor on passenger vehicles and the battery temperature sensor on Jeep & truck vehicles) between 4°C (40°F) and 32°C (90°F) for 0.040 leak. Between 4°C (40°F) and 29°C (85°F) for 0.020 leak.
Engine coolant temperature within: -12° to -8°C (10° to 18°F) of battery/ambient.

NOTE: If battery voltage drops below 10 volts for more than 5 seconds during engine cranking, the evap leak detection test will not run.

Battery voltage between 10 and 15 volts.
Low fuel warning light off (fuel level must be between 15% and 85%).
MAP sensor reading 22 in Hg or above (This is the manifold absolute pressure, not vacuum).
No engine stall during test.

NOTE: The following values are approximate and vehicle specific. Use the values seen in pre test/monitor test screen on the DRBIII® See TSB 25-02-98 for more detail.

A DTC will not set if a one-trip fault is set or if the MIL is illuminated for any of the following:

Purge Solenoid
All engine Controller Self Test Faults
All Cam and/or Crank Sensor Faults
MAP Sensor Faults
Ambient/Battery Temperature Sensor Electrical Faults
All Coolant Sensor Faults
All TPS Faults
LDP Pressure Switch Faults
EGR Solenoid Electrical Faults
All Injector Faults
Baro Out Of Range
Vehicle Speed Faults
LDP Solenoid Circuit

Fig 1: Identifying EVAP Leak Detection Test Sequence

Courtesy of DAIMLERCHRYSLER CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Enabling Conditions To Run EVAP Leak Detection Test

Use the Manual With the Right Hardware

When to See a Mechanic