on my 82 xe, at the front of the rocker cover there is 1 metal 90 degree tube and 2 hose coming off that which run down 2 the carby. this thing has a valve inside it. when i block the hole the engine revs harder, gains bout 100-300 rpm what is it and what does it do???

 

 

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Supplies vaccum to carby?

EGR Valve?


Im only used to seeing an xe with a 351 in it

PCV valve. If it is rattling try replacing it. It picks up revs when you disconnect it cos you basically have a vacuum leak. Gotta have it and a breather tho or crankcase pressurises especially if engine is a bit old......also the cops like to see it therr for emission reasons