Knocking noise from Valve Cover

JohnLeMieux

JohnLeMieux

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Driving my 2006 4.0L Inline 6 Yesterday, I started hearing a knock while accelerating, know I hear it while idling. About 160k miles on it and a brand new timing chain and assorted parts that come with it. I brought it to my mechanic and he said it was likely coming from the valves, but he would need to take off the valve cover to diagnose it. Said he couldn’t get it in for two weeks. Wondering if anyone has heard the same thing or had the same issue. Video attached is it at Idle and while pulling the throttle. Link:
 
JohnLeMieux said:
I brought it to my mechanic and he said it was likely coming from the valves, but he would need to take off the valve cover to diagnose it. Said he couldn’t get it in for two weeks.
Click to expand...

You should a) stop driving it until you figure out what is happening, and b) pull the valve cover and take a look. It might be something simple, it might be about to launch a pushrod. If it's not in the top end, you likely have bigger issues. Also, a better video would be helpful, like one going slowly around the engine compartment and maybe under to isolate the sound. You can also isolate the sound with your ear and a big screwdriver.

BTW, is your oil level fine?
 
BlueC said:
You should a) stop driving it until you figure out what is happening, and b) pull the valve cover and take a look. It might be something simple, it might be about to launch a pushrod. If it's not in the top end, you likely have bigger issues. Also, a better video would be helpful, like one going slowly around the engine compartment and maybe under to isolate the sound. You can also isolate the sound with your ear and a big screwdriver.

BTW, is your oil level fine?
Click to expand...

The oil level is fine, same with the oil pressure. I am gonna do an oil change just to see what happens. I’ll try to get a better video. Sorry again. Thank you for your help
 
Sounds like my old engine every time I had a broken piston skirt (3 to be exact). If you got the tools, might be worth dropping the oil pan when you do the oil change just to check.
 
joe98tj said:
Sounds like my old engine every time I had a broken piston skirt (3 to be exact). If you got the tools, might be worth dropping the oil pan when you do the oil change just to check.
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Having dealt with broken piston skirts in the past I thought the same thing. I would check the oil pan if it were me.
 
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Difficult to determine exactly where the noise is coming from; might be a thrown rod bear, might a piston skirt or possible even a collapsed lifter.
The easiest and first step in your troubleshooting of the noise should be to remove the valve cover and do an inspection of the rocker arms and push rods.
Have a someone assist you and briefly start the engine with the valve cover removed (oil will leak onto the engine) to do an inspection of the rocker arm/pushrod movement.
Listen at the exhaust pipe for a popping sound which might indicate either a collapsed lifter or worn camshaft lobe.
Further investigation will be needed depending upon what your rule out and what other symptoms you find.
 
CharlesHS said:
Difficult to determine exactly where the noise is coming from; might be a thrown rod bear, might a piston skirt or possible even a collapsed lifter.
The easiest and first step in your troubleshooting of the noise should be to remove the valve cover and do an inspection of the rocker arms and push rods.
Have a someone assist you and briefly start the engine with the valve cover removed (oil will leak onto the engine) to do an inspection of the rocker arm/pushrod movement.
Listen at the exhaust pipe for a popping sound which might indicate either a collapsed lifter or worn camshaft lobe.
Further investigation will be needed depending upon what your rule out and what other symptoms you find.
Click to expand...

*hopefully oil will leak onto the engine…
 
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