Mystery Valve
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Mystery Valve
I have a 2002 civic Sir, does anyone know the purpose of the small valve atop the coolant inlet arremby part # 19350-PRB-A00. The valve screws into the assembly and has 2 lines going into it, one from the side that connects to the air inlet tube and another on top that connects to the intake manifold. There are no electrical connections and the valve is not a seperate part as far as Honda is concerned even though it screws into the assembly. It is made of plastic and has broken causing obvious vacuum issues that affect idle. If it is part of the PCV system can I bypass it? Thanks in advance for any help.
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Re: Mystery Valve
Think It's a thermal valve. Think what is called hot wax inside. As it heat, it open. You can replace that part with the vacuum hose can't you? See if just that part is aftermarket..If you can't afford the $99, I would at least hook the two vacuum hoses together rather then have a vacuum leak. Pretty sure that would be what happens when motor is hot. However not sure and I do not have a 202 manual
Last edited by RIPSAW; Dec 28, 2016 at 07:18 PM.
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Apparently it's called and idle assist valve and seems to have little purpose aside from helping the engine heat up a bit faster, I blocked off the hoses and covered up the valve body and car runs great.
