CNG DIAGNOSIS AND REPAIR
For every task in CNG Diagnosis and Repair, the following
safety requirement must be strictly enforced:
Comply with personal and environmental safety practices
associated with clothing; eye protection; hand tools; power equipment;
proper ventilation; and the handling, storage and disposal of chemicals
in accordance with local, state, and federal safety and environmental
regulations.
| VI. CNG DIAGNOSIS AND REPAIR |
|
| A. Diagnose & Repair Supplemental
Systems |
|
| 1. Interpret and verify complaint;
determine needed repairs. |
P-2 |
| 2. Analyze symptoms and perform diagnostic
procedures on vehicles with supplemental on-board diagnostic computer
support systems. |
P-2 |
| 3. Diagnose and repair no starting, hard
starting, engine misfire, poor driveability, power loss, poor mileage,
and emissions problems on vehicle's OEM and supplemental sensors (e.g.,
manifold skin temperature, intake air temperature, natural gas tank
temperature). |
P-2 |
| 4. Diagnose and repair no-starting, hard
starting, engine misfire, poor driveability, power loss, poor mileage,
and emissions problems on vehicles with supplemental computer support
systems (e.g., timing modification devices, ignition interrupt). |
P-2 |
| 5. Diagnose and repair intermittent or
complete failure of electric, electronic or mechanical devices (e.g.,
hour meters, fuel level indicators, fuel selection devices). |
P-2 |
| |
|
| VI. CNG DIAGNOSIS AND REPAIR |
|
| B. Fuel Storage and Delivery |
|
| 1. Interpret and verify complaint;
determine needed repairs. |
P-2 |
| 2. Check all fuel system components to
include fuel lock-off, valves, solenoids, manual shutoff, connections,
fittings, hoses, and tubing for leaks, wear, installation and proper
operation; repair or replace as needed. |
P-1 |
| 3. Diagnose the cause of abnormal fuel
flow through fuel carrying component. |
P-2 |
| 4. Diagnose the cause of fuel odor or fuel
loss by inspecting or testing the fuel supply system components such as
valves, fuel supply container, pressure relief device (PRD), tubing and
hoses; repair or replace as needed. |
P-2 |
| 5. Diagnose the cause of inaccurate fuel
level indicator reading; service, adjust, repair or replace as needed. |
P-2 |
| |
|
| VI. CNG DIAGNOSIS AND REPAIR |
|
| C. A/F Management |
|
| 1. Interpret and verify complaint;
determine needed repairs. |
P-2 |
| 2. Diagnose hot or cold no-starting, hard
starting, poor driveability, incorrect idle speed, poor idle, flooding,
hesitation, surging, engine misfire, power loss, stalling, poor mileage,
and lean or rich mixture problems on vehicles with variable or fixed
venturi type fuel systems; determine needed repairs. |
P-2 |
| 3. Diagnose hot or cold no-starting, hard
starting, poor driveability, incorrect idle speed, poor idle, flooding,
hesitation, surging, engine misfire, power loss, stalling, poor mileage,
and lean or rich mixture problems on vehicles with fumigation or
injection type fuel systems; determine needed repairs. |
P-2 |
| 4. Inspect and test cold enrichment system
components; adjust or replace as needed. |
P-2 |
| 5. Inspect and test fuel injectors;
service or replace as needed. |
P-2 |
| 6. Inspect and test vacuum and electrical
components and connections of fuel system; repair or replace as needed. |
P-3 |
| 7. Perform diagnostic procedures on
vehicles with on-board computer/electronic fuel system support. |
P-2 |
|
