bcampbe7

2012 with about 46500 miles

bcampbe7

Without looking at the truck again, the dealer is telling me that it is probably the IWE solenoid which is not covered under warranty.

I bought a vacuum pump and found some instructions online for testing various items within the IWE system. Problem is that the instructions are for trucks older than 2012. It seems that the solenoid for the '12 is next to the brake booster? Is that correct? Is there still a resevoir box under the battery?

With the truck at idle, I am getting 17"/Hg at each IWE actuator. When testing the actuators, they hold vacuum. If I disconnect the solenoid and put the vacuum pump on the hose leaving the solenoid to the wheels, it holds vacuum.

Where are the check valves for the IWE system on the 2012+?

Below is a pic of the solenoid that I think is for the IWE. This is on the driver's side firewall. For reference, you can see part of the brake fluid reservoir in the bottom left of the pic. When I pull the bottom hose with truck off, a pretty good amount of air rushed out. Is that normal? System holds vacuum when off? Or does that indicate that the solenoid is faulty?

bcampbe7

Ordered a solenoid from the dealer. $20 part so not a big deal.

Why does this noise start when the brakes are applied for the first time? Maybe it's just coincidence as I do have to use the brakes shortly after leaving my driveway.

Another thing I noticed last night while troubleshooting this is that the vacuum at the IWEs would spike to around 23-24" Hg when the engine was revved in neutral and stay there till I pulled the vacuum gauge. Did this on both sides.

Ford850

Check out this video on how to test the components to find the source of the problem.

bcampbe7

Thanks 850. The only thing I didn't do that was described in this video is bypass the solenoid. Having a 2012 I do not see a solenoid on the passenger side firewall as described in this video and every other IWE vacuum thread I have found. I assume the IWE solenoid on the 2012+ is in a different location (see my pic above).

lowd77

I've had this same problem for the last 3 years. Dealer replaces an actuator and all is well until the next winter comes along...and starts all over again. The problem seems to come back every winter. My solenoid is on the driver side as well. Let me know if changing the solenoid helps. No more warranty for me so I'm on my own.

bcampbe7

The 2012 solenoid doesn't have the water cover like the re-designed solenoid on earlier F150s yet the 2012 solenoid is still subject to water intrusion where it is located.

Either that or water is getting into the actuators, freezing and causing damage to the actuator itself.

I am also wondering if the actuator is leaking while under way but not while stationary. Is that even possible? Would there be a way to rig up a vacuum gauge and drive the truck?

bcampbe7

Been awhile since I have updated this thread, but wanted to provide an update so that anyone searching this issue has some form of remedy.

The noise is definitely the IWEs partially engaging. Since my original post, I have had the IWEs replaced 3 times (2 on one side, one on the other). The grinding noise returns after a few months.

From researching this issue, i have found that alot of folks have issue with the plastic vacuum line going across the front of the crossmember. It is prone to being damaged by road debris. I have disconnected the vacuum line off of the solenoid so that the IWEs are always engaged and haven't had the grinding issue since. My plan (when I have the time) is to replace all of the vacuum lines with copper tubing (found someone on a Raptor forum that did this). That has seemed to fix the issue with these fragile plastic vacuum lines.

clm65

Not sure it is the same thing, or if mine is really fixed, but I'll offer up my experience. My 2010 was having intermittent rattling up front. To me it sounded like a loose piece of sheet metal vibrating in the wind. Went on for years, but only maybe 2 -3 times a year max, only between about 40 and 55 mph, and only for about 30 seconds or less each time. Finally I read some threads on the IWE trying to engage and figured that is what I'm hearing. I tried the vacuum pump test procedure. Everything held fine - IWEs, hoses, solenoid valve, and check valve. I even removed the check valve and blew into it to make sure it was holding. A few weeks ago I was putting together an order through Tasca Parts, and figured I would go ahead and replace the solenoid valve and check valve, as they are cheap (<$25 total) and lots of people found these to be their issue. So after I replaced them, I was playing with the old check valve (alternately blowing and then sucking) and every once in a while it would stop functioning as a check valve. So hopefully the old check valve had an issue that periodically showed up. I know it is too early for me to call my issue resolved, but I am optimistic. If you haven't done it yet, I would replace that valve (it is right below the solenoid valve) before replacing anything else. Good luck!