Bought a replacement PCV valve from Autozone the other day and finally got around to installing it. The one I removed had only one port for a vacuum line, but after pulling the new one out of the package it had two (F shaped). Me being inexperienced installed the new one anyway, but now the top vacuum port (smaller one) on the new valve is sucking in air. I guess my question is should it be capped, have a line running to it, broken off, or left open? The truck/motor in question is a 1990 F250 with the 5.8 351w. Any help would be greatly appreciated.

 

Ok so I've been doing more research, but am still confused. From my understanding the pcv valve I bought is more of a universal one and should have come with a cap for the top vacuum line. Mine did not though. So before I do something stupid and break something I would like to get some reassurance that it should have a cap there.

 

There should have been a small plug in the package to block it . Often attached to the valve itself , must be broken loose and installed . Either way , plug it or cap it .

 

Just cap the extra port won't hurt a thing, often the top port universal PCV valve is plugged end of it has to be clipped off if needed.

Sounds like you didn't get that style so a short section of appropriate sized hose with bolt to plug the end will work in a pinch until get a cap for it, or as a permanent fix depends on how fussy one might be about something like that.

 

Toss that one and get a motorcraft pcv valve. Much better quality, and no extra ports. I got a new rubber grommet for the valve cover too, made a nice air tight fit.

Tanner

 

Headed to the store now to buy the motorcraft one. Thanks for the help everyone

 

I always try to use OE motorcraft parts if at all possible and affordable.

 

Motorcraft only! Other junk, aftermarket PCV valves aren't calibrated correctly and can produce a lean condition or worst!