F150 Ecoboost Forum banner

21 - 36 of 36 Posts

·
Registered
Joined
·
7,030 Posts
This can totally be in my head but ever since I threw on the brown pcv valve into my 2011 the truck never felt right. I performed many kam resets etc and nothing changed. Power actually seemed to go down. So I dug deeper.

I gathered some very information from a Ford Technician regarding the tsb and what changes it made. He states these engines are very sensitive to changes. On the brown pcv valve for the updated ecoboost, Ford actually reduced the size of the hole for crankcase evacuation to decrease the amount of blowby going back into your intake. But what they failed to mention was that reducing the hole increases crankcase pressure. With this change required them to reflash the trucks ecu. While they were at it they reduced the amount of fuel used on start up to warm up the cats to aid fuel dilution.

He recommended to anyone with a 11-12 to stick with the black pcv unless you have the tsb performed. He said not all trucks exhibit the fuel in oil issue and that most that were affected were in wet/cold climates.The amount that goes through is presumably compensated for in the ECU somewhere. If you change the calibrated orifice , the compensation probably adjusts just fine - but some trucks behave different than others. 13+ trucks must use the now standard brown pcv valve as with any newer ecoboosts.

Ever since I heard that I threw the black pcv back in and my truck was back to normal.
Hmm. Curious about that. I went to the brown valve years ago and have never had fuel in my oil after the addition of the catch can. However I've always seemed to have a rough idle with it. But PCV really has nothing to do with idle, which sensor is pulling the pressure or vac reading due to this smaller orifice?
 

·
Registered
Joined
·
368 Posts
Well the reasoning behind the rough idle is because the newer(current) pcv valve actually stays open more than the black PCV at idle. With the high vacuum the truck produces the black pcv valve remained closed which led to the crankcase not venting properly etc after a hard run.More noticeable in cold/wet/humid climates. Due to the different plunger and spring rate the pcv valve now stays slightly open. The truck will think theres a vacuum leak. Overall you can easily run the new pcv without a reflash. The only change you may notice is the slightly elevated idle rpm. But I havent tested if maybe an idle relearn can compensate for it.

The newer pcv valve actually helps tremendously with the blowby the truck produces as its evacuating the crankcase more frequently than before. Not only that but its supposedly less prone of leaking when in boost.
 

·
Registered
Joined
·
368 Posts
To update from my last post >>>>>

Doing a idle relearn DOES in fact fix the high idle, but your fuel trims will still be slightly off at idle. Which is no big deal.

Final say, there is no harm in running the updated pcv valve without the reflash. I highly recommend doing an idle relearn/ KAM reset following the change.
 

·
Registered
Joined
·
368 Posts
So i was bored this past weekend and it got me thinking about this thread again. I know I know it’s a very old thing to talk about. I think these engines never actually were “filling” the crankcase with fumes or not evacuating enough.

After finding out the black pcv valve had the slightest leak when pushing 16-17psi it leads me to believe that some boost was leaking into the crankcase. But a VERY VERY small amount. If you had your old one laying around you can test the amount by blowing very hard into it. I think this so called “overfilled” dipstick reading was the side effect of the boost leaking into the crankcase. Giving a false reading of overfilled fuel.

After letting the truck sit for 10 min the level was normal. Even checking in the morning the level was normal. BUT checking a minute or two after shutdown gave off the False reading. Again this very small amount of air leaking isn’t dangerous at all as the Clean air side easily handles the evacuation. That also explains the bit of oil pooling in the driver hot side pipe. It would also explain the different plunger sizes and shapes. The brown updated pcv fixed/minimized the “boost leak” that pushed some oil into the hot side pipe. While allowing the crankcase to vent more efficiently under high vacuum and cruising speed.

Funny thing being is I notice a big difference when running the black valve to the brown valve (on my setup). More pep and smoother idle. Not only that but KR is considerable different. Based on the plunger and orifice size/design. Leads me to believe that the black actually evacuated the crankcase very very well and did a great job on keeping oil from passing. Also keeping the mixture correct.

Im very tempted to test this on my raptor and make the switch in the next hour.
 

·
Registered
Joined
·
1,618 Posts
Discussion Starter #25
I think this is causing me to collect so much in the catch can I have on my CSS. I am running the black PCV still and definitely can "smell" the truck more when idling or stopped. If I blow on it, in the opposite direction it does leak. The brown one does not, it's more like a check valve.
 

·
Registered
Joined
·
368 Posts
I’m more so convinced they designed it (black pcv) to restrict back flow and not fully block it off like a check valve. If it were a problem I think trucks would be blowing seals left and right pulling off the lot.

You of course CAN run a check valve in front of the black pcv so that guarantees max flow and max back flow blockage.

I know some mustang owners in the past actually ran this pcv to help with blowby etc.

Who knows...
 

·
Registered
Joined
·
1,618 Posts
Discussion Starter #27
I dunno, I've been on the black for about a month now and I think I am going to switch back to the brown to see if I collect less on the CSS side. I shudder to think just how much of this condensate was dousing my air filter.
 

·
Registered
Joined
·
368 Posts
I just learned some very interesting things regarding the black pcv valve. Since its the same pcv valve used in the 3.7 i was able to gather more information and it makes a lot of sense.

The design with the black pcv was to restrict the flow when idling which resorted to less oil/blow by consumption when idling. Yet it was designed to effectively evacuating the crankcase over a range. So in theory Which explains the different KR readings I observed. With my inter cooler acting like a big catch can and having a weep hole. I was effectively keeping my intake stream very clean(Well somewhat clean).

But Ford redesigned the pcv to now fully evacuate the crankcase at idle yet having the ability to restrict airflow under very high vacuum. They also designed it to now close with a very low cracking pressure (hence the larger plunger base) Meaning it’s not evacuating over a wide range like it used to. With that change I notice my part throttle KR was all over the place. Ultimately the pcv is now evacuating a bunch of blowby all at when at rest/idle rather than over a range.

With this change it stopped the amount of oil going into the intercooler which is good thing BUT instead of having the blowby evenly evacuated, it now dumps only thru the pcv side.

So if you think about it, Ford engineers did in fact take into consideration for the blowby created with these engines from the beginning. They effectively reduced the amount of blowby from entering the engine all at once but did not fully stop it. Hence why ecoboosts have lower carbon deposits compared to other manufacturers. Somewhere along the line this concern went away and changes were made. (Valve cover baffle and hi flow pcv)

Yes these engines have blowby (as does any engine) but it’s not the amount you are usually accustomed to in a VW/Audi/BMW etc.

I’m not trying to start another war at all. I basically wanted to share my observations as this has really been on my mind for a while.
 

·
Registered
Joined
·
1,618 Posts
Discussion Starter #29
So which one is better? Evacuation over the entire range or high at first and decreasing as vacuum goes up?
 

·
Registered
Joined
·
368 Posts
Evacuating over a wide range will always be better. Hence why I threw my black pcv back in my 2011. Gained a lot of my drive ability back and the idle was VERY smooth. Also the power felt like how an ecoboost should feel. Not only that but I had little to no oil on the end of the pcv hose after the switch back.

Ford switched to evacuating at idle as the now GEN 2 motors incorporate some sort of baffling on the valve cover. My ranger and raptor both have baffling.
 

·
Registered
Joined
·
1,618 Posts
Discussion Starter #31
I wonder if the question is still relevant when running a catch can?
 

·
Registered
Joined
·
7,030 Posts
Evacuating over a wide range will always be better. Hence why I threw my black pcv back in my 2011. Gained a lot of my drive ability back and the idle was VERY smooth. Also the power felt like how an ecoboost should feel. Not only that but I had little to no oil on the end of the pcv hose after the switch back.

Ford switched to evacuating at idle as the now GEN 2 motors incorporate some sort of baffling on the valve cover. My ranger and raptor both have baffling.
I'll switch mine back and see if it helps the idle.
 

·
Registered
Joined
·
5,188 Posts
Are you sure it moves fuel trims? The idle issue may just be because it has changed but will adapt. These trucks are speed density, so nothing should need a retune.
 

·
Registered
Joined
·
368 Posts
Yeah when running the brown pcv valve without the flash. The fuel trims will actually add fuel to compensate for the added airflow at idle. Nothing wrong with that at all.

We’re not talking about a crazy amount of air flowing thru. But enough to raise the idle.

Doing a kam reset does fix the high idle, but you’ll notice the LTFT a tad higher than originally with the black pcv due to it now being open. The truck does adapt but I’ve always had a slight rough idle. Switching back fixed that immediately.


Also to anyone running a mega catch can or Rx catch can, I highly recommend not gutting the pcv valve. The way the aftermarket check valves work is they do a good job blocking boost from going into the manifold but they do not have the ability to restrict the flow under high vacuum. Meaning it will suck up oil. So do not be fooled if all of a sudden you have a large amount of oil in your catch can. Because that is actual engine oil.

So far the only catch can you can gut the pcv valve on is with the FullRace catch can. Since they remove the intake manifold connection.
 

·
Registered
2013 Ford F150 XLT 3.5 Ecobeast SuperCrew 4X4
Joined
·
612 Posts
@SrpRacing OK then, on a stock gen 1 3.5 eco, would you change the original PCV with the black or the newer brown one ?
 

·
Registered
Joined
·
368 Posts
Either will do fine. But if you do a lot of short trips and/or live in a cold climate. I recommend running the brown.

If you are running a catch can, I recommend running the update pcv also. They way they updated it, allows most if not all blowby gasses to only come out of the passenger side.

With the black pcv, ford designed so that the driver side actually spent the majority of the time evacuating the crankcase. Hence the amount of oil in the intercooler. It was there way of keeping the amount of blowby being released from affecting the fuel mixture and overall drivability of the truck.

A crazy thing I discovered the other day was that the 11-12 f150s with the 3.5 actually have baffling on the passenger side valve cover. However the 13-14 do not.

After further research and comparing strategies... there is no issue at all running either pcv. You must however be up to date on the strategy for your truck.
 
21 - 36 of 36 Posts
Top