Important Preliminary Checks
| Action
|
Before performing Symptom diagnosis
| Before performing Symptom based
diagnosis you must perform the
Alternative Fuels (AF) Powertrain On Board (OBD) System Check
.
The OBD system check will determine the following:
- The control modules (AF ECU and VCM / PCM or ECM) and the MIL
are operating correctly.
- There are no DTC's stored.
- Scan tool data is within normal operating range. Refer to
Engine Scan Tool Data List
.
Several of the Symptom diagnostic tables require that a Visual and Physical
Check be performed. Always perform a Visual and Physical Check before using
a Symptom diagnostic table.
|
Visual and Physical Checks
|
| • | Check the control modules (AF ECU and VCM / ECM or PCM) ground
connections for being clean, tight and in the correct location. |
| • | Inspect the gasoline control module (VCM/PCM or ECM) for the correct
Bi-fuel calibration. Program the gasoline control module if necessary. |
| • | Check the vacuum hoses for leaks, restrictions and proper connection
as shown on the vehicle emission control information (VECI) label. |
| • | Check for any type of fuel leak or fuel line restriction. |
| • | Check for air leaks at all areas of the intake manifold sealing
surfaces. |
| • | Check for proper installation of the gas distribution adaptor
(GDA). |
| • | Check for air leaks at the GDA. |
| • | Check the ignition wires for the following conditions: |
| • | Check vehicle wiring for the following: |
|
Symptoms
|
- Verify the customer concern.
- Locate the Symptom table that indicates the customers concern.
- Check the items indicated for that symptom.
The following Symptom tables are located in this section:
|
