Q: How to check the PCV valve and filter on an engine?
A: If there is rough idling in the engine, it might be caused by a clogged PCV valve, filter of hose. The PCV valve of a four-cylinder engine is located in the rubber elbow near the Throttle Body end for a rubber hose that connects rocker arm cover to the throttle body. The PCV valve filter is situated between air cleaner snorkel and rocker arm cover. While the engine is idling at normal operating temperature, remove the PCV valve hose plastic fitting from its rubber grommet in the rocker arm cover and place your finger over the end of the PCV hose fitting to test for intake manifold vacuum. If there's no vacuum and engine speed doesn't drop, you should check out your hose first. If you have a clear tube, inspect it for any damages or breaks such as splits on its surface or holes on one side only. If these checks go well, go ahead and look at your PCV filter. The inside can be cleared; therefore, if this doesn't work either, then maybe you need to examine the valve itself. Switch off all engines and take away that rubber elbow; it should come off easily without much effort needed. A ball within the valve may rattle during shaking; otherwise replace it too if it happens not to rattle or even make slight tickling sounds when shaken. When buying another PVC valve, ensure that it is suitable for your car model year and engine type too. Push in on this new valve until it bottoms out into housing (elbow) making sure that it faces inwards like before when you were removing old one from throttle body tube leading downwards towards crankcase breather hole adjacent bottom bracket mounted around front right corner underneath engine compartment top cross member support bar used previously holding linkage together securely during operation before wrecking anything else whatsoever by mistake while performing necessary procedures like replacing worn-out bushings along lever arms assemblies since they are not readily available from dealerships anymore). Don't install reverse flow of PCV valve because it won't operate correctly. While the new piece is being slid into the other end, this clamp will be tightened properly. If there is need for a change, replace it with damaged rubber grommet at rocker arm cover. Press it on over fitting at throttle body side and insert plastic fitting at opposite end of PCV hose back through grommet in rubber elbow where it belongs. In a V6, you'll find the same procedure for testing that valve although it's hidden amidst the rear cover crowed between two flaps connected by a band which makes them slightly movable only if lifted outwards together due their interlocking shape so as to provide better seal against any leaks; outside panel also has its own separate opening thus offering an ideal place where one may access inside system if needed most efficient way when compared other locations where such parts are placed around engine block itself either right behind passenger's front fender or left near driver side firewall beneath battery box besides which there shouldn't exist any further difficulties trying work within narrow spaces since these sections occupy significant volume so even reaching them requires extra few steps ahead further making task easier than anticipated otherwise resulting damage caused during previous attempts carried out incorrectly anyway affect overall performance vehicles overall condition including various systems comprising including ignition timing components like spark plugs; apart from these other devices fitted elsewhere under hood of respective makes models years gives directions based personal preferences for instance Vortec engines use small filters e.g., AC Delco PF61E oil element made paper media surrounded metal cannister structure containing several orifices soot particles while diesel fuel filter smooth running vehicle maximize economy enhance power output minimize emissions improve overall quality life users while maintaining longevity proper operation everybody involved correct manner not jeopardizing durability plus avoiding possible failure leading unexpected breakdowns causing its owner embarrassment besides, many companies produce wide range different types brands filtration products marketed all over world today some famous names globally known such as Bosch, Honeywell/AlliedSignal (FRAM), Denso, Mahle, Mann Hummel Purolator amidst others. The other end system plugs into top front valve cover.