Caution: Avoid breathing fumes and swallowing EGR exhaust deposits when removing
components for cleaning as bodily injury may result.
Whenever the exhaust gas recirculation (EGR) valve is removed the EGR system
should be inspected and cleaned if necessary. This will ensure that the EGR system
will function properly under all operating conditions. Proper EGR system service consists
of the following 5 steps:
- EGR system diagnosis--Diagnosis of the EGR system should be performed
if powertrain control module (PCM) DTCs are set .
- EGR valve pipe cleaning and checking for leaks--Clean and check the
EGR pipe from the exhaust manifold to the EGR valve and the EGR pipe from the water
pump crossover to the throttle body spacer. Refer to
Exhaust Gas Recirculation Pipe Replacement
.
- EGR valve cleaning--If the EGR system is operating correctly, the
EGR valve can be removed, checked for deposits, cleaned, and re-installed. Use the
procedure below for this operation.
3.2. | While holding the EGR valve in your hand, use a pencil eraser or other
suitable soft instrument to depress the pintle several times. The pintle should move
in and out smoothly. Replace any valve that exhibits tendencies to stick. |
3.3. | While holding the EGR valve base in your hand, try to rotate the connector
housing. Repeat for the coil housing. Replace any valve that exhibits looseness. |
3.4. | Inspect the EGR valve pintle and seat for deposits. Use a cloth or other
suitable soft device to remove deposits. Remove all loose particles. If the deposits
are such that pintle/base interface cannot be cleaned adequately to allow the pintle
to seal against the seat, replace the valve. Damage to the powdered metal EGR valve
base will occur if cleaned with solvents, sharp tools, a wire brush or wheel, or by
sand blasting. Cleaning by these methods is not recommended. |
3.5. | Inspect the passage in the water crossover assembly for deposits. Remove
all loose particles. |
- Cleaning the EGR passages in the water crossover assembly.
4.2. | Remove the 2 plugs (2) and clean the passages with a wire
brush. Remove all loose particles. |
- Wash-up with soap and water after any contact with deposits from the EGR
system.