I read this forum several times from front to back since I had the same IWE issues. Dealer wanted $220 to DIAGNOSE! I vacuum tested the actuators (they held)... replaced the solenoid..did not fix. Replaced 1 check valve...still wasn't the issue. I began testing each section of vacuum line and even pulled out and tested the reservoir, until I found it!!! I found a severed brittle line that leads to the actuator was broken. It was right where it leaves the engine compartment into the wheel well. A little bandaid patch with another piece of vac tubing solved my issue. $0 Fix!!! I hope I haven't done too much damage grinding on the actuators, but at least I found my issue. I super appreciate the detailed info in this forum!!!

 

Good on you!

I believe the most common cause of a vacuum problem is a deteriorated hose. It seems we often overlook the simplest solution when we troubleshoot because we start out thinking the problem must be caused by something complicated.

Of course I started driving back when windshield wipers were vacuum driven. I've had many vacuum line failures over the years.

- Jack

 

Hi,
I have a 2010 F150 STX and am experiencing what sounds like the exact same problem people are describing with the vacuum system. Runs fine in 4 wheel drive rattles in 2 wheel, but only when accelerating. My question is since I have to manually shift into 4 wheel drive, as opposed to a dash button, is the system still vacuum operated?
Thanks in advance,
Tim

 

Welcome to the forum, Tim! It sounds like a trip to the dealer is in your future; I know they'll be happy to track down that rattle for you. How many miles are on your truck?

Crystal

 

Changing spark plugs (went as planned, thank god)
• On test drive I immediately heard what sounds like a rattling sound in my left front tire like a IWE actuator going bad.

• The switch inside the cab will light up 4x4 High but not 4X4 Low.'

• Jack it up both wheels spin freely when in 2wd. they do.

• I have the car running (on jack stands) switch it to 4WD and I did not see the axle shaft and the IWE moving together when in 4x4 high.

• In 2013 the passenger side actuator went bad. Took it to a shop they replaced the solenoid with the old style one. They replace the switch inside the cab and the IWE actuator on the passenger side. Sounds like the same type of rattling sound.

• I pulled a used solenoid off a (06) F-150 in a U-PULL-IT yard but it still did the same thing free wheeled in 2wd. But I did not see the axle shaft and the IWE engaged when switched to 4W High on both sides of the vehicle.
still not sure.
ps. Is there a hose on the back of the intake manifold for the IWE on the 2005 models? check this guys video out. Not sure where that is located.

 

Maybe it's because of the holiday weekend, thats way no one is responding to my post.
Some one has got to know where this hose is located in a picture of a exploded view. thanks everyone in advance.

 

gibby, I know there is a hose back there but I am not sure where exactly it pulls vacuum from. I would get a vacuum gauge and unplug the check valve near the PCM and stick your gauge on there. If you draw constant vacuum above 20 then you shouldn't have anything to worry about in regard to that hose. Just my $.02 hope it helps

 

Just wanted to say that FORD did a great job at engineering their IWE. OF course a Dealer would love to see you. I have 61,000 miles on my FX4 Crystal and am about to replace the actuators AGAIN!

FORD TOUGH, is easy to say.... HOW ABOUT BACKING IT UP WITH A 100,000 mile warrantee to prove it!

 

Hi brianm1a,

I definitely understand how multiple repairs can be frustrating. If you'd like, I can document your feedback. Just PM me your full name, best daytime phone number, VIN, and any details you'd like me to include. I'll take it from there.

Crystal

 

Had a rough idle for awhile. Initial thought was vacuum leak.
Later heard grinding on the left front while turning.

Based on this thread:

Disabled IWE system till I could get to it (disconnect and then plug line at vacuum switch).

In less than 30 minutes I narrowed it to a leak in the vacuum line at the first body tie about 8" up from the left side IWE. Cut the bad section and spliced in both the vacuum actuator and vent lines.

According to the auto parts store receipt, the vacuum line is 4mm ID and the vent line is 3mm ID. I had them pull an IWE and test the fit before leaving. One foot each and some plastic vacuum line splices and the system holds vacuum for over 20 minutes (key on, engine off).

Note, engine has been idling smooth since the IWE disable (plugged) and then the fix.

** I now keep a vacuum cap w/ the spare fuses in the glove compartment in case I'm somewhere and need to disable the IWE system **.

Thanks for the excellent writeup.

 

That is interesting...my truck idles rough...haven't thought to check IWE's...I'm at 181k miles so that could be a possibility...I think the lines all tie in behind the battery with a single line running to the brake booster...

 

xjcamar089 I have a post [2003 front end not engauging] if I'm understanding you correctly if everything else is working and I disconnect the vac lines to the front wheels they should ingauge.
I have also heard that there is a shifting fork inside the Differential that maybe broke, is that true?
If not and I unplug the vac lines on the wheels and the 4x4 still doesn't work what else is there to look at?

 

Does anybody know if this is the same way the 2015+ works? I'm wanting to set up the front end so I can engage/disengage it while still in 4lo. I had this on my previous truck and it is so nice to use 4lo to move a trailer around.

Thanks!

 

Good day! I have a 2005 F150 XL 4wd maual shift and since the winter I have had an issue shifting out of 4wd into 2wd. The light on the dash goes off, then after a couple of seconds I get a loud bang. Took it to a mechanic and he said it was the transfer case so I ordered a used one off ebay had it installed and still same issue. He next stated it was the solenoid and actuators. Put them on and still same issue. I next found this post and discovered my first check valve was bad between intake and second, replaced that same issue. I next discoverd that my vacuum box was bad where I had previously blew out the lines, replaced that same issue. I have perfromed all of vacuum test listed in this posted, and do not believe I have a vacuum leak. Only thing I havent done is replaced the lines. I can shift it into 4wd drive, drive, stop disengage it back up and it doesn't do it; however, if I disengage it stopped and go forward or at a low forward speed i hear a terrible bang. It sometimes also does it when engaging. Any help would be appreciated, I am at my wits end.

 

For the sake of others with this problem I figured I'd post my experience.

I started hearing the grinding noise a while back. Googling pointed to the IWE issue and I took the truck into the dealer yesterday. I told them what it seemed like it was and they said "Yeah, we've seen that issue".

They called me back and said they checked the IWE and it/they? were fine. They tried to reproduce the issue in a road test and couldn't. I went back in and took the tech for a drive and indeed, could not make it happen - grrr.

Driving the truck back home, about a mile from my house, it happened. I have no idea if this is relevant but it only happened *after* i filled up with about 40 gallons of gas. Perhaps the added weight in the truck was enough to make it happen more. I know that it was awful when pulling my Travel Tralier and would only go away if I switched to 4A.

Anyway, I went back to the dealer and took the tech for another drive and he heard it. I left the truck and today they called me and said it was fixed. Yeah, replaced the IWE actuators.

I'm not quite sure why they said they were fine before and only after hearing the noise did they find that they were bad. I gently questioned them on this and all they said that the noise helped them pinpoint the problem area. Hmm.

Everything was covered under my warranty although I'm not sure if it was through my extended warranty or a standard one.

This is a 2012 F150 Lariat SCREW.