Chevrolet Cobalt Service & Repair Manual: EGR Functional Tests
Fuel Injected Gasoline Engine
| The EGR systems used on fuel injected
engines are controlled by the ECM. The ECM will store a code in memory when
the EGR system malfunctions. Refer to appropriate "Diagnostic Code Identification
Chart" for code number. |
Linear EGR Valve
| 1. |
Connect Tech 1 Scan Tool, or equivalent,
to DLC following tool manufacturer's instructions. |
| 2. |
Correct any DTCs that may be present,
particularly those pertaining to MAP sensor fault conditions. |
| 3. |
Start engine and operate at approximately
1500 RPM, then select MISCELLANEOUS TEST, EGR CONTROL with scan
tool. |
| 4. |
EGR valve should cycle through 25%
through 100% positions. |
| 5. |
Engine RPM should drop and idle should
roughen as EGR valve is cycled. |
|
PCM & ECM Controlled EGR Valve
| This EGR system is controlled
by ECM or PCM, which will store a code in memory when EGR system is faulty. |
Gasoline & Alternative Fuel Engine Vehicles
Visual Inspection
To ensure proper operation of
all emission control system components it is required to perform a visual
inspection. R ...
Change Oil, Change Oil Now Or Change Oil Soon Messages
After changing the engine oil,
the system must be reset as follows:
1.
Turn ignition to RUN with en ...
See also:
Chevrolet Cobalt Owners Manual. Antilock Brake System (ABS)
The vehicle might have the Antilock Brake System
(ABS), an advanced electronic braking system that
helps prevent a braking skid.
If the vehicle has ABS,
this warning light on the
instrument panel comes
on briefly when the
vehicle is started.
When the engine is started, or when the vehicle ...
Chevrolet Cobalt Owners Manual
Chevrolet Cobalt Service Manual