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Discussion Starter #1
so i got a small knock at around 1.5-2k rpms
but the thing is its only there when the cars warms up

also my car still runs fine has like 157k miles just that lil knock i wanna know what it is hope its nothing major

and it doesnt even kncok all the time its random times i hear it
also its not a loud knock just a soft lil knock

any help guys plz :)
 

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hold the revs there with a buddy or with your other hand and one by one go down each bank and undo a coil. Listen to see if the knock softens or goes away. When you remove the spark, you remove a metric **** ton of force on that specific rod/piston/bearing and will great reduce the knock sound if its in the rotating assembly, except if its a main bearing, but thats not too common on these cars for failure points.
 

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hold the revs there with a buddy or with your other hand and one by one go down each bank and undo a coil. Listen to see if the knock softens or goes away. When you remove the spark, you remove a metric **** ton of force on that specific rod/piston/bearing and will great reduce the knock sound if its in the rotating assembly, except if its a main bearing, but thats not too common on these cars for failure points.
+1 I had the same noise. Turned out to be rod knock.
 

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It might also be a lash adjuster (lifter). If a lifter goes bad they tend to knock until the car is warmed up and the oil is flowing good.
 

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Discussion Starter #8
How much it cost u to get that rod knock fixed ?
And thnx bro ima try that yomorow abd hope its not a rod knock lol :)
 

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As eagle said, it could also be a last adjuster. Its not hard to pull the valve covers, take them off or the one on the side you hear the noise from and wiggle each arm. If a lash adjuster is worn, youll have slop in the follower/rocker
 

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It's hard to explain but a lifter knock and a rod knock sound differently. A rod knock has a deeper tone. It's not a sound you forget once you've heard it. My experience (five motors) is that a rod knock does not go away. A lifter knock will when engine is warm the oil starts flowing good. I had an old Chevy truck where the lifter only knocked during the winter. I just let it warm up before I drove it. I drove it that way probably five years before I got rid of it.
 

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depending on the wear of the bearing. I tore down an engine for a customer, he HULK SMASHED the number 4 rod bearing, but would only make noise at 2500 and above and caused massive missfires.

But normally its an all or nothing or is frequent enough where you dont have to wait but a min or two and you will hear it again.

The rod/main nock has a solid deep sound to it where as a lash adjuster/lifter has a more tinny pinging sound to it when they collapse
 

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Yea mines was more of the deeper sounding knock. It started at about 1900 rpm's then it just got worse.
 

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That is more of the symptoms of a rod knock. I once was running my '69 Camaro hard down some windy roads. I went into an S-Curve. Downshifted to third, powered through the curve but the second half was on me too fast. Went to second. The motor screamed but I got through the curve. I cheared for about 30 seconds. That deep sounding knock started at 2500 rpms... It wasn't the first time I had heard it so I tried to drive below that... it then went to 2000... 1600.. I was pretty much at idle when I got home.

That sound is unique above all others and it just puts a sad, sickening feeling in my stomach every time I hear it.

Edit: We used to call a tapping lifter a tappet. That's for hydraulics. Solids make an entirely different racket of their own.
 

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I couldn't hear it very well but it kind of sounded more like an exhaust tick than a rod knock.
 

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Discussion Starter #18
Hmmm well idk that noise did pop up after i put my new exhaust in . Idk man i just know i gotta fix it :/
It bothers meh lol
 

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sounds like an exhaust leak to me also :dunno
 

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that's exactly the noise I have in my car right now. I pulled the plug on my coils one at a time and the drivers side rear coil once unplugged the knock was gone... I have a bad feeling about my issue, hope yours isn't the same as mine....
 
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