EGR System Cleaning

EGR Control Valve Cleaning


Caution: Do not wash any EGR valve in solvents or degreaser, as permanent damage may result, also, sand blasting of the valve is not recommended, since this can affect the operation of the valve.

Caution: Wear approved eye protection for this cleaning procedure, to avoid possible injury to the eyes.

Clean the control valve as follows:

1. Disconnect vacuum hose from EGR valve, then remove EGR valve-to-manifold retaining bolts, and the control valve.
2. With a wire wheel, remove the exhaust deposits from the mounting surface and around the valve.
3. Open the control valve, with an external vacuum source, and check for excessive buildup of carbon deposits. Anything more than a thin film is excessive.
4. Using a suitable sharp edged tool, scrape the carbon deposits from the control valve poppet. Do not scratch the valve seat or dislodge the poppet from its stem.
5. Check for wear of the poppet valve or stem, if any is noticed the control valve should be replaced.
6. Install new gasket, then install the control valve.
7. Reconnect the vacuum hose to the control valve.




Intake Manifold Cleaning

Note: When cleaning intake manifold EGR passages, care should be taken to ensure that all loose particles are completely removed to prevent them from clogging the EGR valve or from being ingested into the engine.

Caution: Do not use drills or wires to clean carburetor control passages as calibration may be altered and result in poor engine performance.


1. Disconnect vacuum hose from EGR valve, then remove EGR valve-to-manifold retaining bolts, and the control valve.
2. Scrape carbon deposits from the EGR port using a suitable sharp edged tool. Use a wire wheel and brush all of the deposits off of the valve mounting surfaces.
3. Blow deposits from EGR ports and control passages using compressed air.
4. Install EGR control valve, using new gasket.
5. Reconnect EGR vacuum hose