AWD actuators making noise 2008

[William_ff]

The front AWD actuators aren't fully engaging or disengaging. I found some stuff relating to the F150 and it seems right on with the actuators themselves, but I can not find the vacuum solenoid. Also the symptoms are slightly different. Here is the scenario.

In 2WD start driving and get the noise.
Switch to AWD noise goes away and then comes back.
Switch to 2wd noise stays, switch to AWD goes away and comes back.
Also while in 2wd with the noise, switching to cruise control it goes away and comes back.

From the F150 stuff I've seen it is more set than this. Since it can go away and come back seems it might not be the AWD actuators themselves but the thing controlling them.

Thanks,
Will

 

[deweysmith]

On the 3rd-gen the solenoid for the vacuum-actuated hubs is on the firewall above the brake booster on the driver's side. I would bet you have a vacuum leak or a bad solenoid. I think the hubs are unlocked with no vacuum, so it's probably a bad solenoid. It seems that it can pull vacuum for a second or two to lock the hubs, but the vacuum leaks down after a while and it partially unlocks again. The noise might be caused by the solenoid not closing fully either, allowing a little bit of vacuum down to the hubs so they are always half-locked.

I dunno a ton about them though, other than where the solenoid is.

 

[William_ff]

That is the solenoid that is named Canister Purge Solenoid / Purge Valve, right? The one for the F150 is called Solenoid, 4WD Engage And Emissions Purge or IWE Solenoid.

So the Canister Purge Solenoid / Purge Valve is what I should replace? Just confused on the names.

 

[William_ff]

I disconnected the hose from the solenoid and nothing changes. It is like it has nothing to do with the system.

 

[deweysmith]

This is the electrical diagram for the engine compartment in the service manual for my 2012. You can see the electrical connection for the solenoid in ~C6 in the grid, I circled the label. It's called the Integrated Wheel End Solenoid in the manual.

Again, this is on a 2012, 2008 should be similar.

The Canister Purge Solenoid is part of the EVAP system and lives right behind the intake on my truck, you are correct that it is entirely unrelated to the 4WD system… It's connected to the vacuum system to pull fuel expansion vapors from the gas tank and push them through the intake.

 

[William_ff]

I found another vacuum solenoid around there, but that isn't it either. I can't even find a part for an 08. I only can find it for up to 06 and then nothing at all for an 08.

Example: https://www.1aauto.com/4-wheel-driv...MI6K2hx_Tk1wIVlArTCh3l2AOIEAQYASABEgIPcvD_BwE

Vehicle Fit

• 1997-2006 Ford Expedition 4 Wheel Drive Engage Solenoid
• 1995-1996 Ford Explorer 4 Wheel Drive Engage Solenoid
• 2004 Ford F150 Heritage Truck 4 Wheel Drive Engage Solenoid
• 1997-2013 Ford F150 Truck 4 Wheel Drive Engage Solenoid
• 1997-1999 Ford F250 Light Duty Truck 4 Wheel Drive Engage Solenoid
• 2006-2008 Lincoln Mark LT 4 Wheel Drive Engage Solenoid
• 1998-2006 Lincoln Navigator 4 Wheel Drive Engage Solenoid

 

[deweysmith]

Here is the part listing on fordparts.com for a 2008, which includes the exploded diagram.

How did you determine that wasn't it? You should see two hoses coming from it, and they end up at the wheel hubs. It's possible that you have a bad hub, too. Simple test, do the hoses on all ends of that solenoid hold vacuum when you suck on them with your mouth? They're dirty on the outside, sure, but they should be clean on the inside. If they do, it's not a leaky hose, and it's either a bad hub, or a bad solenoid. It could also be low engine vacuum but you'd surely have other symptoms aside from this.

 

[deweysmith]

Check out this video from FordTechMakuloco. He explains how to diagnose it… The only difference should be that the solenoid is on the driver's side, not the passenger side. It's behind the coolant bottle and the brake fluid reservoir. You can see the same hose connections and check valve in the video connected to it, and the part number on the solenoid on mine is 9L14-9H465-BA. Here it is on mine:





Also, I was wrong. Vacuum unlocks the wheels, there's a check valve there to maintain the vacuum and keep the hubs released, even when the engine is off. Try the video's method, bypass the solenoid entirely and see if the clicking stops. Try as the video suggests, disconnect the hoses, and attach the hose that goes to the hubs directly to the check valve and run the engine (go for a spin, even) and see if the clicking stops. If it does, bad solenoid. If it doesn't, bad hub.

 

[William_ff]

I do not have that. I have something similar right there and it always has a vacuum on the hose and on the other side of the solenoid. I think it is the brake booster. I will go take a picture.

 

[William_ff]

The top solenoid is the evap. The one to the lower right of it always has a vacuum going through it.