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Seriously...Odd Piston Slap Starting.

Hack

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I wonder whether lugging the engine at 50-60 mph in 6th gear can slightly collapse the piston skirts and that's why some people have this. Or people just interpret sounds differently. Or the normal variations from part to part means that some people got lucky.

I don't believe I have piston slap. I've had a vehicle with piston slap before, so I know what it sounds like. I've run my car in below zero weather, and I think it would have happened at that time more so than at normal temperatures. I even asked a coworker who used to work as an engineer at an engine testing facility what he thought and he said no he couldn't hear any piston slap.

I don't have oil consumption either. I have no idea if there's a link or not.
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Offboost

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Maybe the thinner piping of the new exhaust is allowing more sound to emit from the pipes that the stock pipes did a better job of keeping quiet.
 
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galaxy

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If it is knocking sound I would have the dealer look at it. That could be a precursor to engine failure according to my mechanic. I am no expert - just passing on a comment he made about hearing pistons knocks like you describe may be something to check on
My shits not going to the dealer for this. If it's an impending engine failure, I'll take it in when it gets there, LOL. If such is the case, that train has left the station that a trip to the dealer will not prevent.

I am at over 10k miles now, no problems, rattle has not gotten worse... Just cope with it.
Oh yea, I agree. While it is annoying, especially adding in the facts it started later and started in conjunction with something else, it's just messing with my head, LOL. But yea, nothing I'm losing sleep over or will start selling this car down the river over.

Maybe the thinner piping of the new exhaust is allowing more sound to emit from the pipes that the stock pipes did a better job of keeping quiet.
Yea, I actually thought of that one, believe it or not. The only thing that in my mind rules this one out is the fact (like I originally stated) that the noise was not immediate with the exhaust install. I would have noticed. It was a short time after, but not immediate with.

I'm just mainly trying to come up with anything/everything I can do to rule out the exhaust. I've been back under it a few time and cannot find a rattle or any problem with exhaust. Thanks guys.
 
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galaxy

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So I'm gonna call it official on the piston slap. Basically had the entire exhaust out (to swap x-pipes) to rule out any rattle. Inspected everything, rehung the exhaust, it's solid as can be. First drive, no change. I'd say this ruled out any exhaust rattle or the like.

I guess the only question I'm left with is...is it worth anything to take it to a dealer to let them hear it, make their own diagnosis, and document it? The assumption is the info is there and they're not going to do anything anyways, but curious if the documenting is even worth the trip and the effort.
 

Austinj427

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So I'm gonna call it official on the piston slap. Basically had the entire exhaust out (to swap x-pipes) to rule out any rattle. Inspected everything, rehung the exhaust, it's solid as can be. First drive, no change. I'd say this ruled out any exhaust rattle or the like.

I guess the only question I'm left with is...is it worth anything to take it to a dealer to let them hear it, make their own diagnosis, and document it? The assumption is the info is there and they're not going to do anything anyways, but curious if the documenting is even worth the trip and the effort.
Because Ford already has a TSB out for it, I'm not sure it would do anything.

If it makes you feel better you can do it though.
 

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torque124

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I don't think there are cars that don't have it at all, just people that don't listen or hear it over the exhaust.
 

rj45

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My car also has what most here have described over the last couple of years as piston slap. It hasn’t gotten worse or changed significantly. If you believe this is the issue, a trip to the dealer is likely a waste of time. Plus, there’s a good chance they’ll say that they can’t duplicate the noise, which it’s only gonna piss you off.

If in the future something goes wrong and the car has no warranty denying mods, they’ll likely fix it without grilling you about symptoms. And if they do, Ford says piston slap/rattle is normal for this engine. My $.02
 

johnny1

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Not true not all cars have it. My 16 never had it and my 17 doesn't. And you know if you have piston slap especially in the cold winter. When you start car you will hear it knocking and the knock gets more rapid as you accelerate till starts to warm up and it disappears. My 2005 GTO had it and I'd drive slow for about a block in fear of throwing a rod or something. When I traded that car years later it still did it exactly the same. There are many documented cars with it and even after high mileage engine was just fine. Its not going to do any harm to engine period!
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