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Discussion Starter · #1 ·
Hey Everyone - my ride has developed a new noise that is driving me crazy and i cannot find it.

Remember on old cars how if they alternator was going bad you could hear it through the radio as a subtle RPM dependent whine? This is exactly like that, except the radio doesn't have to be on, and it only shows up when I'm on the the throttle.

If i'm going 70 down the expressway, leave it in gear, and coast with the elevated RPM it goes away, but as soon as I blip the throttle it is back. I have found lots of posts about strange whines, however none seem to fit the bill exactly so I figured I'd post it up. Sorry if this is a repeat!

Thoughts?
 

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Take a long screwdriver and touch the alternator and other belt driven item and put your ear to it. Have someone raise the throttle.

Sent from my XT1585 using Tapatalk
 

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Does it change with speed, the faster you go the faster the noise gets or does speed not affect it. Could be the sound symposer though.
 

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If there is a serpentine belt tensioner, check that. When you blip the throttle it comes back and thats when the belt gets pulled but the tensioner has to keep it in check.
 

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Hey Everyone - my ride has developed a new noise that is driving me crazy and i cannot find it.

Remember on old cars how if they alternator was going bad you could hear it through the radio as a subtle RPM dependent whine? This is exactly like that, except the radio doesn't have to be on, and it only shows up when I'm on the the throttle.

If i'm going 70 down the expressway, leave it in gear, and coast with the elevated RPM it goes away, but as soon as I blip the throttle it is back. I have found lots of posts about strange whines, however none seem to fit the bill exactly so I figured I'd post it up. Sorry if this is a repeat!

Thoughts?
Did you happen to install a new motor mount recently?
 

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Check your grounds.
 
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Discussion Starter · #9 ·
Does it change with speed, the faster you go the faster the noise gets or does speed not affect it. Could be the sound symposer though.
The noise/ whine gets higher pitch with RPM On the throttle for example, it is higher pitch at 3500 RPM than 2000 RPM, but at both 3500 and 2000 RPM goes away without throttle. Also, cannot be replicated without moving, which is why i didn't think it was tensioner related.
 

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New motor mounts and transmission!
Which motor mounts? Brand/location

Maybe something is rattling or rubbing that wasn't before, did it start happening right after that install?
 

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Discussion Starter · #11 ·
Which motor mounts? Brand/location

Maybe something is rattling or rubbing that wasn't before, did it start happening right after that install?
Honestly it wasn't for a few weeks after the install that I noticed it. I will have to check my repair order, the dealer changed them out while they were dealing with my transmission on warranty.
 

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Honestly it wasn't for a few weeks after the install that I noticed it. I will have to check my repair order, the dealer changed them out while they were dealing with my transmission on warranty.
They break in after a little bit of driving, that could be a potential thing to look for/at. Does this noise still happen when you are idling and rev? Or is it only in gear? If it's only in gear then transmission could be worth questioning. If it happens when revving regardless of neutral/in-gear then stand outside your car and have someone rev it. If it sounds like it's in a particular part of the engine bay then that can help diagnose.
 

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Discussion Starter · #13 ·
They break in after a little bit of driving, that could be a potential thing to look for/at. Does this noise still happen when you are idling and rev? Or is it only in gear? If it's only in gear then transmission could be worth questioning. If it happens when revving regardless of neutral/in-gear then stand outside your car and have someone rev it. If it sounds like it's in a particular part of the engine bay then that can help diagnose.
I can only hear it while moving, and location isnt perceptible. This transmission is definitely "whinier" than my last one, especially in 3rd and 4th... but also shifts 10x better than the one the car had out of the box so I havent really questioned it. My thoughts were if it were hardware related (such as the trans itself) it wouldn't be so sensitive to the throttle?

Just spit balling it, wouldn't the dependancy on throttle position indicate a:

A) Plumbing Leak
B) Boost Problem
C) Angering the ghost haunting my car

I've been wrong before, and I'm sure I'll be wrong again... I've seen me do it.
 

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I can only hear it while moving, and location isnt perceptible. This transmission is definitely "whinier" than my last one, especially in 3rd and 4th... but also shifts 10x better than the one the car had out of the box so I havent really questioned it. My thoughts were if it were hardware related (such as the trans itself) it wouldn't be so sensitive to the throttle?

Just spit balling it, wouldn't the dependancy on throttle position indicate a:

A) Plumbing Leak
B) Boost Problem
C) Angering the ghost haunting my car

I've been wrong before, and I'm sure I'll be wrong again... I've seen me do it.
Well I'm sure if a few people who are knowledgeable of the platform or these kinds of issues rode in your car they would be able to help more but without hearing this whine really all of us are taking guesses. Hopefully it's something small. You within warranty? You could just have Ford take it for a ride and let them deal with it
 

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Discussion Starter · #15 ·
You within warranty? You could just have Ford take it for a ride and let them deal with it
Oh yeah I'm within warranty - however - I don't know if its Ford or my Dealer, but I get the classic "concern cannot be replicated" and in regards to the other strange noises I have "thats normal, should have bought a car with more insulation" and "not covered because you hit a pothole" (just to name a few of my favorites)

..and I digress, thats why I found this place :)
 

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Discussion Starter · #17 ·
Well, had a break thru. It appears a (possibly the) noise was coming from the new transmission. Engine took 3 tries to start (fairly common btw) and when it started there was a god awful noise under the hood that went away when I press the clutch to the floor. As soon as the clutch is let out the noise came back. I have video if anyone wants to see, just advise how to share on here.

Took it to the dealer, their diagnosis was "its broken, will be a while to fix" and I got shook down for $410.03 for a rental car while it sits in line waiting to get fixed. Thanks Ford Warranty...

Side note, before I start a new thread, anyone have experience with doors randomly flying open? My base focus rental car has a driver side rear door making for an interesting time.
 
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