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Discussion Starter #1
Interesting story from my weekend. My '13 SE has 103000 miles on it or so.

Noticed the car was boggy off low throttle last week. Figured the TCM was acting up so re-cleaned all my ground connections and even added a 2FT ground cable from the main ground down to the TCM ground under the airbox. (I think it goes to the TCM)

Car ran amazing for 100 miles. Accelerated nice and hard from a dead stop. Saturday I realized I left my PCV hose disconnected from the intake. Re-connected it and the low throttle bog came back although more intermittent.

So I pulled the hose and sprayed it out with maf sensor cleaner and boom car has been running amazing ever since. I don't even really understand how or why it worked cause the hose wasn't clogged... it was just dirty. [confused]
 

w/ my magic bag
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Possibly the pcv valve itself.....Basically the combustion gases that go pass the rings, valves,ect go thru the pcv valve which then get reburned...The older vehicles had a down draft tube which the byproduct escaped to the atmosphere......
 

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Discussion Starter #3
Possibly the pcv valve itself.....Basically the combustion gases that go pass the rings, valves,ect go thru the pcv valve which then get reburned...The older vehicles had a down draft tube which the byproduct escaped to the atmosphere......
I figured that might be a possibility but just cleaning out the hose did the trick.
 

Ford Fiend
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Are we talking about the breather hose here? From the valve cover to the intake?
 

w/ my magic bag
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Anyone happen to know the workings of the pcv system? What it does & why?
 

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I replaced my whole PCV valve and hose around 90K miles I think. Got that nice CEL for a few months during winter and my MPGs dropped like crazy combined with below freezing temps and winter gas (averaged like 21MPGs @75mph driving from CO -> IL once.)
 

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Discussion Starter #13
I replaced my whole PCV valve and hose around 90K miles I think. Got that nice CEL for a few months during winter and my MPGs dropped like crazy combined with below freezing temps and winter gas (averaged like 21MPGs @75mph driving from CO -> IL once.)
So where is the valve? lol
 

Ford Fiend
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In general a PCV vents your crankcase gases back into the intake. On motorcycles we usually remove the entire system.
More specifically, it vents positive pressure crankcase gasses back to the intake. But, the section of hose that you cleaned out was just the "clean side" of the PCV system that, for the most part, just equalizes crankcase pressures. I've never seen any buildup in mine, so I'm surprised by your results.

So where is the valve? lol
The valve is on the "dirty" side of the PCV system, and it is mounted in the top of the oil separator that is between the block and the intake manifold.
 

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Discussion Starter #16
More specifically, it vents positive pressure crankcase gasses back to the intake. But, the section of hose that you cleaned out was just the "clean side" of the PCV system that, for the most part, just equalizes crankcase pressures. I've never seen any buildup in mine, so I'm surprised by your results.
Well I mean it's obviously a thing when people can install catch cans and collect a bunch of gunk. That being said, anyone know the best catch cans to use with an SE? [hihi]
 

Ford Fiend
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They only catch gunk on the PCV valve side, not on the breather side, and that is why the oil separator is there. It is a difficult job to install a catch can on the valve side. There was a recent thread where we discussed this ad nauseum. If you install it on the breather side, you will mostly trap water vapor, which isn't an issue.

It might be a "thing" for some people, but it never has been for my 94K miles SE. I have very low oil consumption though.
 
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