Knocking Noise Upon Cold Startup

[2010 Eddie Bauer]

I have a question for you all. When it is well below freezing outside, I will get a knocking noise from the front of my engine. It sounds as if it is coming from the bottom half of the engine. It only occurs upon a cold start first thing in the morning. I have the 4.0 sohc V6 with approximately 105,000 miles on the clock. It lasts for approximately a minute or so before it goes away. It does not occur upon every cold start, but does most of the time. It disappears upon putting the transmission into drive. I bought it used with 85,000 miles and have changed the oil every 3,000 miles with Mobil One full synthetic since I have owned it. I heard of the dreaded timing chain problems and installed a pre oiler about a year ago to prevent issues. This noise still occurs after the engine is pre-oiled. What could be causing this?

 

[Mbrooks420]

Pre-oiling doesn’t guarantee you won’t have issues. I’d post a video of the sound and one of the SOHC guys can tell you if it’s the tensioners or not.

 

[donalds]

A video would be great

 

[2010 Eddie Bauer]

A video would be great

I will get one when I can. Believe it or not, it has to be under 27 degrees Fahrenheit to hear the noise. It will be a few days before conditions permit.

 

[Mr. Alligator]

What oil weight are you using?

 

[2010 Eddie Bauer]

What oil weight are you using?

5w-30.

 

[2010 Eddie Bauer]

A couple of example Timing rattle videos,
1st is not too bad,
2nd is much worse.

It does not sound like either. It is not a rattling sound. Rather, it is a "knock--knock--knock--knock sound.

 

[2010 Eddie Bauer]

20201228_090849.mp4

drive.google.com

It finally did it again this morning. This site would not let me upload the video because the file size was too big, so I uploaded it to Google Drive and shared it via this link. Thank you all for your time and trouble.

 

[donalds]

Don't sound like timing to me....look up and say thank u Jesus...
Sounds like a bearing imo
Or front jackshaft tensioner maybe imo
As Mr Brooks said pull the belt and start it

Only let it run for 30sec or less

 

[Mbrooks420]

Pull the belt and see if it still does it next time.

 

[2010 Eddie Bauer]

A bit of an update: the idler pulley had too much play in it, so I replaced it this afternoon. The tensioner and belt are new. I will see if the sound persists tomorrow morning or if it is gone.

 

[michael loibl]

Check the harmonic ballancer pulley as well

 

[Mitchs07explorer]

I have the same exact issue going on with my 07 4.0 with 150k on it. Just started last year, first noticed it in the earlier part of the year Jan/feb, disappeared over the spring/summer and then as soon as temps where around freezing the ticking would show up again. Never did it right at startup but after idling for 30 seconds to a minute I get an intermittent tick, sometimes consistent sometimes not. I’ll also also try to upload a recording. I just replaced my belt, idler pulley, tensioner pulley, spark plugs, plug wires and did an oil change with full synthetic 5w-30 and motorcraft oil filter which is what I always use. When it warms up it goes away and won’t come back unless it sits overnight and it’s below freezing. Otherwise, when it’s warm the engine sounds like it’s practically new.

 

[Mitchs07explorer]

Just listened to the video, the ticking sounds just like mine but mine doesn’t do it as consistently for that long.

 

[2010 Eddie Bauer]

I have the same exact issue going on with my 07 4.0 with 150k on it. Just started last year, first noticed it in the earlier part of the year Jan/feb, disappeared over the spring/summer and then as soon as temps where around freezing the ticking would show up again. Never did it right at startup but after idling for 30 seconds to a minute I get an intermittent tick, sometimes consistent sometimes not. I’ll also also try to upload a recording. I just replaced my belt, idler pulley, tensioner pulley, spark plugs, plug wires and did an oil change with full synthetic 5w-30 and motorcraft oil filter which is what I always use. When it warms up it goes away and won’t come back unless it sits overnight and it’s below freezing. Otherwise, when it’s warm the engine sounds like it’s practically new.

I am beginning to think it is my harmonic balancer pulley. It wobbles slightly when I look at it through the passenger-side wheel well with the engine running.

 

[michael loibl]

Stick your finger inside the bolt hole in the front of ballancer with engine off and see if the metal weight is loose.

 

[Mitchs07explorer]

I am beginning to think it is my harmonic balancer pulley. It wobbles slightly when I look at it through the passenger-side wheel well with the engine running.

Any luck with figuring out the noise?

 

[2010 Eddie Bauer]

Any luck with figuring out the noise?

The harmonic balancer has been replaced but the noise still persists. I have ordered both the front and rear timing chain tensioners from Ford, but they will not arrive until Mid March. The noise still does not occur if the temperature outside is in the upper twenties or above. Regardless, I think it is good preventative maintenance to get both tensioners changed out. If that solves it, I will post to this thread. If not, I will look at the fan clutch/water pump. That is the only pulley I have not been able to check for certain at this point.

 

[michael loibl]

The harmonic balancer has been replaced but the noise still persists. I have ordered both the front and rear timing chain tensioners from Ford, but they will not arrive until Mid March. The noise still does not occur if the temperature outside is in the upper twenties or above. Regardless, I think it is good preventative maintenance to get both tensioners changed out. If that solves it, I will post to this thread. If not, I will look at the fan clutch/water pump. That is the only pulley I have not been able to check for certain at this point.

Remove the serpentine belt and then start the car on a cold day and see if noise goes away