Mine was the line 2013 f150 3.5 eco crew BL3Z7A785A
TSB-ABI32235 think 2010-2014??

https://www.f150forum.com/f38/7-week...-parts-382153/

 

i drive a 2010 f150 fx4 5.4
i started hearing these whining noises, brought it to Ford they said my actuators were bad. Awesome they replaced both but the noise didn't go away. I brought it back and they said two techs drove around in the truck and didn't hear anything. (i must be going crazy) i drive to work and i hear the noise definitely around 40mph+ randomly, it goes away if i let off the gas or accelerate, i also hear no noise in 4wd though(like at all). I've ordered that check valve and solenoid hoping that's the problem. I did hook up a vacuum pump, one of those hand pumps and it certainly did not hold vacuum at all(if i did it correctly). I've kind of hit a wall if anyone has any suggestions.

 

Glad I found this. Torn my passenger side apart 4 times now, 4wd actuator went bad. Replaced with new Dorman unit, still grinds. Been driving me absolutely nuts. 2010 F150 XTR 5.4. Checking that valve out tomorrow.

 

Replaced check valve at solenoid, fixed issue.

 

Mine was the check valve also. Dealer said the check valve was fine. i pulled it off and could suck air thru both directions.

 

Makes you wonder sometimes what these Dealers really are capable of. If they cant even determine a $7 check valve is bad...i sure as hell don't want them diagnosing the rest of my truck

 

My '13 FX4 eco is going in again for the same issue. It was "fixed" a month ago.

 

The lack of any type of mechanic skills displayed by some dealers/their techs can be truly phenomenal. Everything I've read over the years say the good techs always go to a private shop or start their own shop. Dealers are full of rookies and guys that can't make it on their own. Every now and then there's a good tech that is paid well enough to stick around for decades and you are one lucky SOB if you find that particular dealer/technician.

 

Removed the check valve in mine and it was open in all directions. Replaced both IWE, compressed air thru lines to clear out dirt and used brake cleaner and compressed air to clean out check valve. All is now good! I can only assume that the ruptured IWE allowed engine vacuum to draw dirt into the check valve.

 

Yeah, and for every master tech that makes his own great shop, there's about 20 crap shops where they're probably half drunk on the job and are worse than the dealer.