Annoying quiet rattle cold engine

Qjoh5510

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Anyone else have a low key quick paced rattle/knocking noise when accelerating with a cold engine? The speed of the noise seems to be in line with engine rpm, goes away when the trans is shifting and comes back while accelerating through the next gear. So it’s only doing it under acceleration and for the first couple minutes when the engine is cold. The noise is totally gone after the engine warms up, maybe like 2 or 3 minutes of driving.
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TravisRogers

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My engine sounds like a diesel when it’s cold. Always makes me cringe. But it also pings when it’s warm. And it drinks oil.

You know how people would put 300K miles on an old Toyota truck and feel bad about selling it because it still ran perfectly? Yeah, this isn’t that.
 

asuperheat

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Maybe Fuel? What grade of fuel are you using?

Kind of sounds like what you are describing is not high enough octane or older fuel that's been sitting. Try a different station and higher octane for a tank and see what it does.

Could be a knock sensor failing.
 
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Qjoh5510

Qjoh5510

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Maybe Fuel? What grade of fuel are you using?

Kind of sounds like what you are describing is not high enough octane or older fuel that's been sitting. Try a different station and higher octane for a tank and see what it does.

Could be a knock sensor failing.
I’ve been running mid grade which is 91 out here. My last 2 fill ups have been 93. I don’t get any pinging or knocking when warmed up. Just this quiet knocking or whatever it is when cold for the first few minutes. It is load based too. The more load I give it the heavier and louder it gets.
 

F-1shakey

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I’ve been running mid grade which is 91 out here. My last 2 fill ups have been 93. I don’t get any pinging or knocking when warmed up. Just this quiet knocking or whatever it is when cold for the first few minutes. It is load based too. The more load I give it the heavier and louder it gets.
I just posted a question regarding a similar issue with my 3.6/6speed. I’m hearing that noise aswell when accelerating cold; but I can also hear the ticking/tapping/knocking when it is coming down from fast idle to normal idle for about 5-7 seconds , are you experiencing this aswell?
 
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Qjoh5510

Qjoh5510

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I just posted a question regarding a similar issue with my 3.6/6speed. I’m hearing that noise aswell when accelerating cold; but I can also hear the ticking/tapping/knocking when it is coming down from fast idle to normal idle for about 5-7 seconds , are you experiencing this aswell?
I’m not sure about the fast to slow idle. I’ll have to check on that in the morning. You’re talking about when you first start the engine and it’s at fast idle and eventually slows down? I’ll pay attention to it in the morning and report back.
 

F-1shakey

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I’m not sure about the fast to slow idle. I’ll have to check on that in the morning. You’re talking about when you first start the engine and it’s at fast idle and eventually slows down? I’ll pay attention to it in the morning and report back.
Yes exactly, as it’s settling down to normal idle speed I’m getting the noise for 5-7 seconds
 

F-1shakey

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I’m not picking up any knocking noises during rpm slowdown after high idle warmup.
alright well thanks for checking anyways, I’m going to be bringing it to the dealer next week to get checked out.
 

TravisRogers

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I run 93 in mine all the time to keep it from pinging. The manual says pinging is normal. Guess that’s easier than fixing it.
 
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