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Cold engine, loud "tick" - Turbo rattle?

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Hello all, just curious if anyone else has this. I am somewhat hesitant to classify the sound as a knock, maybe more of a loud tick? But after letting the ST sit overnight the first start of the morning I get a faint knocking sound at idle that increase in volume just above idle and then fades away as the RPM's are brought up. This noise persists until the engine is completely warmed up. By the time I get to work it's nice and quiet.

I am super OCD / anal about engine noises, I just need a sanity check if this is completely normal or something that should be listened to by the dealer. This is a new '21 with less than 500 miles on the clock.

Thanks for your replies!
 

Mobius87

Mobius87

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Sounds like it may be an exhaust leak to me. We have a similar issue, which is definitely an exhaust leak.

Sent from my SM-G991W using Tapatalk
 

R

rjacobs

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possibly cam chain tensioners. Search a few threads and find one with video and see if yours is similar sound.
 

OP
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Mobius87 said:
Sounds like it may be an exhaust leak to me. We have a similar issue, which is definitely an exhaust leak.

Sent from my SM-G991W using Tapatalk
Click to expand...
I believe this is what it is due to the nature that it goes away after the engine is hot, likely a leak at the manifold to the cylinder. I have schedule a service appointment for Monday morning, will drop it off Sunday night so the tech can get a good listen to it at cold start. Also going to have them inspect the brake pedal situation. I have that annoying "click" and just overall noisy/sloppy pedal.
 

OP
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I never updated this, but the dealer said no exhaust leak on it. This is still annoying me, they claimed they couldn't hear anything but I know that's bogus because it's been annoying me ever since I bought the truck.

After doing more research, it sounds like it might be the wastegate in the turbo's rattling? Has anyone documented this to be something that happens on these? Seems common on a few other Ecoboost models.
 

JohnE

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Check your exhaust flex pipes; one on each side. Mine does it until it’s fully warmed up but it’s more of a rattle than a tick. I got under it and it is for sure the left side on mine. Ford’s fix is a big hose clamp.
 

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Tommyc

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I have a similar rattle sound at cold startup. Not really load but there. Now I have the entire Thermal downpipe back exhaust and it is not emanating from there. I think (not 100%) it is like the the old chokes from my generation where the engine will run rich at initial startup and then restrict fuel after 5-10 seconds. This excessive fuel can cause vibration in the darndest places. It is not like a valvetrain noise (cam phasers) but a rattle through the whole vehicle. Hell with the thermal exhaust the resonance could be the cause but had it even with stock exhaust for 5 seconds. I ignore as all seems good after that. FYI 2021
Tommy
 

ST+

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From what I've read it is the cam phasers which rattle like that when cold. Mine does it too and it goes away soon after as the engine warms. Your dealer should know about this and has probably done some repairs. There are several videos in YouTube. Apparently a lot of 3.5 ecoboost and 3.0 ecoboost engines are having this issue and I believe there is a 'recall' on the 3.5's going back to 2018. I'm waiting to hear of a recall or tsb on our 3.0's

Colin.
 

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I've looked up the cam phaser rattle and the instances I've been able to find seem way different than mine. Mine is a tick that lasts for 5-10 minutes, the cam phasers seem like a really noisy racket for the first 2-3 seconds right after a cold start.
 

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10 Gauge said:
I've looked up the cam phaser rattle and the instances I've been able to find seem way different than mine. Mine is a tick that lasts for 5-10 minutes, the cam phasers seem like a really noisy racket for the first 2-3 seconds right after a cold start.
Click to expand...
good to know -- and I have now read other threads and comments here which shed some light. -- then it seems more likely to do with the exhaust...........also crossed my mind that injectors can make this noise tho usually constantly until cleaned. (with a gasoline dispersed cleaner).
It will be interesting if there is an answer to this.
 

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