midwestern

Hi Everyone,

This is my first actual post on the forum although I've used it as a source of information for a long time. It's a great resource.

I did a search and only came up with a couple of threads concerning this topic. I have a 2013 5.0L supercab 4x4 and I've been having some issues with a strange howling/whistling sound that seems to come and go intermittently. Specifically it's acted up twice in the last two weeks, typically after being stored outdoors overnight. It occurs while in park or in drive at 1500-1800 RPM and then again at around 2200-2500 RPM. Suspecting the water pump I tried spritzing the shaft where it attaches on the back side of the idler pulley and that seemed to help the first time, but not as much the second. As of today it wasn't making the noise which is pretty weird given that I recorded this just yesterday. Any thoughts? Anyone have experience with this?

I attached a sound clip.

midwestern

After a bit of a reprieve the sound returned briefly a couple days ago while the motor was cold and again this morning (louder) on the way to work. It's the first cold morning we've had in awhile (40 F and rainy) so that might have something to do with it. I through my mechanics stethoscope in the back seat but won't have a chance to investigate until after work. Worse comes to worse, I'll take it to Ford.

I guess this isn't that common? I'll let everyone know what I find out.

cmbezln

That's definitely a vacuum leak somewhere. Vacuum system is full of rubber and plastic parts that expand and contract as things warm up and cool down.

First thing to check is in your intake tract....make sure the filter box is clamped down tightly.. Check your worm clamps. Spray some carb cleaner or use torch gas around your throttle body, etc.

midwestern

Thanks for the input ... I guess I was way off the mark on this one. I shouldn't have been so quick to assume it was a bearing issue. During my lunch break I popped the hood in a parking lot and it took me about two seconds to realize the hose clamp for the airbox was loose. I tightened it down with a nickle because it was all I had to use and the noise went away. Hopefully that was the cause. I'll tighten in properly and and go through the rest of the plumbing tonight.

steve392

i had a whistling noise start today. was pulling into work and went to use my keycard to get into lot and i heard whistling. Sounded like a turbo whistle, it would go up in pitch as you accelerated. I could not figure where it's coming from. just started today, 14 5.0 with just under 41k

midwestern

I checked all of the plumbing leading into the airbox and the throttle body hose that I diagnosed yesterday afternoon was all that was loose. I tightened it down properly. During the drive in today there was no noise and it was pretty cold so hopefully I can close the book on this one.

I'm not sure if your problem is related Steve but it might be. My truck wasn't making any noise at idle and only acted up at higher RPMs which makes sense given that the motor in generating more suction under those conditions. That being said, all of the plumbing is right there for you to inspect. May as well have a look ...

Thanks again to cmbezln, I think you saved me a big headache.

cmbezln

No problem man, glad you figured it out. Nice thing about the 5.0s is there's not very many places for a vacuum leak to happen, unlike some turbocharged vehicles ive had in the past (that can be a nightmare).

Steve: I would suggesting doing what midwestern did and just check all connections in the intake tract. Isolate it down to the engine by putting it in nuetral and revving it to make sure it's not a wheel bearing or something screwy. A very tiny tear or pinhole can whistle like a turbo (sort of), so check your vac lines for dry rot etc and replace as necessary.

midwestern

I guess I spoke a little bit too soon. The noise was back on the drive home today. At least my intake hose isn't loose anymore. I'll let you guys know when I get to the bottom of what's causing the noise. All of the plumbing stuff is synced up at this point but I haven't tested it with torch gas yet. That's probably the next step. If that doesn't reveal a problem I'll turn my attention back to the belts and pulleys.

steve392

im going to give a look over tomorrow. I couldn't the last 2 days as I noticed it last night when i pulled into work. Didn't hear it when i left work but it was there when I got home and again when i left for work today. It is there at idle. It sounds like turbo whistle.

cmbezln

maybe double check everything again, could have a bad clamp somewhere. Unless it going away was just totally coincidental, im inclined to think its at least related.