Cadillac 25043843 Valve,Pcv

Start the engine and then stop it. Pull the valve (with hose attached) out of the rubber grommet in either the rocker arm cover or camshaft cover. Put your finger over the end of the valve. Check for a plugged hose, manifold port, or valve itself if there is no vacuum at the valve. Change any plugged or deteriorated hoses' Turn off the engine and shake PCV valve listening for rattle. Fit new one if valve doesn't rattle. To put a new VALVE on pull it out of the end of hose with attention to where and how it was installed. Whenever purchasing a replacement PCV valve, make certain that you are getting one that is designed for your particular vehicle, model year and engine size. Ensure they are similar by comparing old valve with new one. Push in the valve until seated into end of hose. Replace grommet if damaged; inspect rubber grommet for damage and replace as necessary. Push firmly into place PCV valve and hose into rocker arm cover or camshaft cover.

The positive crankcase ventilation system helps to minimize the emission of hydrocarbons by drawing gases from the crankcase then circulating fresh air through the air cleaner then through the crankcase to mix with 'blow-by' gases before being directed by the PCV valve to the intake manifold. These consist of vacuum hoses and pcv valve, the function of which is to control the flow of gases depending on the engine speed as well as manifold vacuum. For maintenance of idle quality the PCV valve restricts flow when the intake manifold vacuum is high, and in an abnormal situation, it permits excess blow-by gases to flow back to the air cleaner for burning. Maintenance check of the PCV system is required because carbon and gunk can clog the valve and hoses resulting to rough idle, stalling, oil leakages, or sludge in the engines. To check vacuum look for the PCV valve filter which is found beneath the rocker arm cover; remove the hose and put your thumb over the end of the hose as the engine runs; a slight vacuum is expected. In case vacuum is low, then it requires more investigation, as, for example, a leaking valve or hose can lead to problems with performance. Shaking the PCV valve should produce a clicking sound; failure to which indicates it's time to replace it. The idiomatic expression 'if you want to fix something you should try breaking it' can be the case here: unlocking the valve and running the engine while attempting to draw suction will work as a diagnostic test: lack of vacuum will indicate a blockage in the hose or fitting. When replacing the PCV valve, the type chosen should match the engin requirement to prevent damage of the engine.

A blocked valve can lead to gas escaping through weak seals, which can cause oil leaks and sludge formation.

After turning off the engine, shake the PCV valve to listen for a rattle; if it doesn't rattle, replace it with a new one.

The PCV valve is typically located in one of the rocker arm covers on the side of the engine.

On a V6 engine, the filter is located at the other end of the system, where it attaches to the top of the front valve cover.

The PCV valve is located in either the rocker arm cover or intake manifold.

Remove the fuel injector cover, disconnect the MAP sensor's electrical connector, unclip the sensor from the PCV valve access cover, and rotate the cover counterclockwise to remove it. Replace the PCV valve, making sure it matches the old one, and install it in reverse order. Replace the O-ring if needed.