Massive Engine Knock on All Startups

[Cdnspeed]

rod knock or a VCT cam gear, if you have no check engine lights, id say its rod knock.

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[Sig556]

I've had the coyote tick lightly but the last few months it has gotten worse. I change my oil every 3k miles and check the level weekly. This video was taken last night after the car sat for an hour after a drive home from work. I believe it sounds like piston slap or a warped sleeve. As soon as the car hits operating temperature around 185 it goes away. The exhaust is not leaking anywhere and I dont beat on the car. Always let it warm up before pulling out of garage. The car has 15k miles on it and would be under warranty except there's a kenne bell on it. Looking for ideas on if my suspicion is correct.

WOW! I don't know for certain but that at first sounds like a rod knock. Then it sounds like something in the valve train. And to have it go away eliminates the rod knock. If you had a spun bearing the rod knock would NOT go away and in fact become more apparent. The only way to be sure is to open that baby up. As others have stated the best course of action would be to return your car back to stock. load the factory tune and hope to have it repaired under warranty. If you cannot go that route and you can afford it I would buy a fresh short block and call it a day. It's NOT going to get any better.

 

[Dark knight s550]

as others have said, maybe take the whole KB kit off and hope for a dealer that wont care/mod friendly and doesn't mention the fact that the car has been flashed before. otherwise build it out to make it a beast if you have the means to do so.

 

[gimmie11s]

Install new stock 15-17 shortblock and done.

 

[Cdnspeed]

Im going to call cam gear phaser/ VVT/ VCT whatever you want to call it

 

[F1scamp]

Sounds like a header gasket leak to me....

 

[96gt4.6]

^ It seems like there is a bit of exhaust leak there for sure, but man I can sure hear a lot of metallic/deep knock. Me personally, I would use a scan tool to cancel cylinders during the noise and see which hole is causing it. Sure sounds base engine......but a video is super hard to diagnose from, however that one sure sounds like an internal engine concern.

Once you identify which hole is the origin of the noise via cancelling them out one by one, the next step I would do is remove the oil filter, and cut it open at the top carefully with either the proper oil filter cutting tool, or I carefully use a cutoff wheel/saw. Pull out the element and look for bearing. If we have bearing, and a noise cancellation then it is most certainly internal engine. If no bearing, but has noise decrease when a specific cylinder is cancelled, then perhaps piston/wrist pin concern, but again would require teardown.

 

[racingmason]

as others have said, maybe take the whole KB kit off and hope for a dealer that wont care/mod friendly and doesn't mention the fact that the car has been flashed before. otherwise build it out to make it a beast if you have the means to do so.

Thought about that but I'm an honest person. Dont they see how many times the car has been flashed regardless of key cycles since the last flash?

 

[racingmason]

^ It seems like there is a bit of exhaust leak there for sure, but man I can sure hear a lot of metallic/deep knock. Me personally, I would use a scan tool to cancel cylinders during the noise and see which hole is causing it. Sure sounds base engine......but a video is super hard to diagnose from, however that one sure sounds like an internal engine concern.

Once you identify which hole is the origin of the noise via cancelling them out one by one, the next step I would do is remove the oil filter, and cut it open at the top carefully with either the proper oil filter cutting tool, or I carefully use a cutoff wheel/saw. Pull out the element and look for bearing. If we have bearing, and a noise cancellation then it is most certainly internal engine. If no bearing, but has noise decrease when a specific cylinder is cancelled, then perhaps piston/wrist pin concern, but again would require teardown.

Oil filter is sitting in the garage. I changed the oil just before the video was changed and sent a sample in to get analyzed. The exhaust is torqued to spec and was checked last week. When I did the kooks headers i used the comtec gaskets and wish I didnt but I check the tightness of the stage 8 bolts monthly. Thinking of getting or borrowing a endoscope to check the cylinders. It's weird how it goes away when the car warms up. I was leaning towards an oblong cylinder and I've read these blocks grow up to 4 thousandths at 200 degrees.

 

[96gt4.6]

Can you post a video after it warms up? It is true, I have had a few that had out of round cylinders, but none have had that much knock/rasp. It could be just the video making it sound worse than it is on this end too.

Scoping the cylinders certainly wouldn't hurt, however I would also highly recommend canceling cylinders to see if you can isolate it to a specific hole for further diagnosis.

 

[racingmason]

Can you post a video after it warms up? It is true, I have had a few that had out of round cylinders, but none have had that much knock/rasp. It could be just the video making it sound worse than it is on this end too.

Scoping the cylinders certainly wouldn't hurt, however I would also highly recommend canceling cylinders to see if you can isolate it to a specific hole for further diagnosis.

Here you go. It's not near as bad but you can hear it.

 

[Boduke0220]

Install new stock 15-17 shortblock and done.

I agree with this. Add some OPG/CS and head studs and send it.

 

[96gt4.6]

From what i'm hearing, there is undoubtedly serious internal damage there. That's not exhaust for sure.

I see you are running 14 psi, what fuel were you using?

 

[Vegas5OH]

Doesn't hurt to check out around the header gaskets though before making any hasty decisions lol.

 

[Tommy V]

Yea i hate to see you tear the motor out only to find out it was header leak.I have heard header leaks sound just like rod knocks.

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