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 inspecting for leaks. Clean and inspect
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, inspected 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.