Reduced Fluid Level In Windshield Washer Reservoir After Vehicle Operation (Remove Reservoir Cap Gasket/Install Check Valve)

Some customers may comment that the windshield (W/S) washer reservoir shows an unexplained reduced fluid level after vehicle operation.

There may be two possible causes.

1. One cause may be that the W/S washer reservoir is not venting properly. The reservoir cap has a slit in the gasket to allow air to enter, but it may have become ineffective. This results in the reservoir being pressurized due to thermal expansion from engine heat. W/S washer fluid will be forced out of the nozzles until pressure is equalized.
2. The other cause may be a low air pressure area at the W/S resulting in a vacuum at the nozzles. This may siphon fluid out of the reservoir.

1. Inspect the W/S washer system. Verify that there are no loose hose connections or leakage from the reservoir and hoses that may contribute to fluid loss.



2. Remove the W/S washer reservoir cap (4).
3. Remove the gasket from the W/S washer reservoir cap and discard the gasket. Removal of the gasket will ensure that the reservoir (1) is properly vented. Fluid retention and anti-splash characteristics will remain unchanged.
4. Install the reservoir cap.

Important: The check valve is designed for fluid flow in only one direction. Make sure the arrow indicating direction of flow is pointing away from the pump.

5. Install a check valve, P/N 22102237, into the W/S washer pump hose (2).

5.1.	Cut the W/S washer pump hose as close to the reservoir as possible.

5.2.	Insert the check valve in the location shown on the illustration and connect the hoses to the valve.

6. Verify proper W/S washer system operation.

Parts are currently available form GMSPO.

For vehicles repaired under warranty, use: