Loud engine noise suddenly.

[dprocket]

My son's 2008 Ford Explorer XLT V-6 has very suddenly started giving very loud engine noise.

He was driving home last night and called me to tell me about it.
I checked it out. Definitely very loud engine noise, like a helicopter taking off. Sounds very bad. It was loud enough that I immediately told him to turn the engine off.

I hooked up my code reader to it and found a P0340 - Powertrain. Camshaft Position Sensor "A" Circuit.

After looking up this sensor, it is inexpensive and only 1 bolt holds it on. I'm certain I can do it myself, but in reading up on the Camshaft Position Sensor, I'm not sure this is the issue. I would love for this seemingly major issue to be a $50 1-bolt sensor, but my gut tells me is not.

Any thoughts?

 

[Explorer_PL]

It's probably the cooling fan reving up. I am not sure about v6, but on my v8 I had to replace the fan clutch assembly with the sensor and wire harness.

 

[dprocket]

It's probably the cooling fan reving up. I am not sure about v6, but on my v8 I had to replace the fan clutch assembly with the sensor and wire harness.

Is there a good way to test this? It was in my garage and it was so loud that I was hesitant to get under and take a look. If I spin the fan, should it spin freely?

 

[07EddyB]

Was it a roaring noise, steady but loud air blowing or was it a mechanical noise?
If it is the fan then make sure your coolant level is good before diving into the fan.

 

[Beachcomber86]

The 06 has known wiring harness insulation failures. Take a look at this thread.

Found my ghosts in the machine

Hey guys, If you've got unexplained, and intermittent, problems, here's a possible cause. My Ex has developed what is best described as the "hiccups" at idle. It doesn't happen all the time, and feels like a misfire. No codes, though. So I thought I'd just inspect the engine for (esp the...

www.explorerforum.com

 

[redheck2017]

I just changed that sensor on my "2007" one bolt, but had to take off the belt and AC compressor because it it is in the way of the bolt coming all the way out.

 

[dprocket]

Was it a roaring noise, steady but loud air blowing or was it a mechanical noise?
If it is the fan then make sure your coolant level is good before diving into the fan.

It sounds like a mechanical noise to me. It's hard for me to describe. Here's a video I took.

VID_20201107_100200979.mp4

Shared with Dropbox

www.dropbox.com

While in the garage, next to my son, it was so loud that I would need to shout to him next to me so he could hear me.

 

[Explorer_PL]

To me sounds like a chain slapping on a timing cover .....

Hope I am mistaken.

 

[Tommylee1282]

If you haven’t already, I would take the serpentine belt off, and briefly run the engine and see if the noise goes away. I agree with explorer_pl, it sounds like a timing chain, specifically the front one, maybe you get lucky and changing the tensioner buys you some time

 

[Leck G]

I’ve read there is a recall for the timing chain tensioner on some years. The part is plastic and is a huge job. The book time is around 8 hours and requires the head to be removed.

 

[dprocket]

I’ve read there is a recall for the timing chain tensioner on some years. The part is plastic and is a huge job. The book time is around 8 hours and requires the head to be removed.

I have not see this anywhere, and a quick search of recalls doesn't show anything. Any more details?