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Stock BOV, is it made of plastic?

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Metro Detroit
#1
Recently with my 2019 I've been hearing a sort of whistle at near idle speeds and the power seems a bit off. Basically the car feels like it's running on 89 octane but the fuel economy lines up with 93 octane that I run in my car. Was discussing this with a friend who has been pretty deeply involved in boosted Fords, he's had a Focus ST and a 1 of 10 off factory built Mountune Focus RS. He stated the factory BOV in his ST was a composite and really wasn't impressed with the Mountune BOV in the RS so he replaced it with a Turbosmart unit.

Anyhow the factory powertrain warranty is still in place, so I'm asking if it's possible that I do have a cracked BOV. Yeah, I know I should go straight to a Turbosmart. The problem with that is I have miles left on my powertrain warranty and this car is starting to have issues that have already needed warranty repair. So I am all for punishing Ford for putting chinese made crap in our cars. I also need to maintain the OEM warranty in the event I need to have the engine replaced under warranty.
 


FiestaSTdude

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#2
Recently with my 2019 I've been hearing a sort of whistle at near idle speeds and the power seems a bit off. Basically the car feels like it's running on 89 octane but the fuel economy lines up with 93 octane that I run in my car. Was discussing this with a friend who has been pretty deeply involved in boosted Fords, he's had a Focus ST and a 1 of 10 off factory built Mountune Focus RS. He stated the factory BOV in his ST was a composite and really wasn't impressed with the Mountune BOV in the RS so he replaced it with a Turbosmart unit.

Anyhow the factory powertrain warranty is still in place, so I'm asking if it's possible that I do have a cracked BOV. Yeah, I know I should go straight to a Turbosmart. The problem with that is I have miles left on my powertrain warranty and this car is starting to have issues that have already needed warranty repair. So I am all for punishing Ford for putting chinese made crap in our cars. I also need to maintain the OEM warranty in the event I need to have the engine replaced under warranty.
It feels like a dense plastic to me. The internals also feel cheap to me if that makes sense, especially compared to the turbo smart bov, which is definitely better quality than the stock one. IMG_20220807_075711335.jpg
 


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Lancaster, PA, USA
#3
There’s definitely been examples on here of the stock BPV leaking.
only other thing I would think of, would be if one of your boost hoses are coming off
 


OP
scooter123
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Thread Starter #4
Thanks for the warning. It means yet another trip to the dealer for another warranty repair. I'm starting to think I should just bite the bullet and order a Mountune MRX long block. The car only has 33-34K miles on it and so far the drivers rear view mirror mirror had the mechanism fail, the slave cylinder jammed, and now the BOV is leaking.
 


OP
scooter123
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Thread Starter #6
Where is the BOV located, front near the intake or at the rear near the turbo? Did take note of more symptoms today. At low speeds on roads with no traffic I can hear a hissing gas release at each gear change, basically a less loud version of boost being vented to atmosphere. At roughly 40 mph in very light traffic I can also hear a very subtle sort of whoosh/hiss that I think may be the boost venting to atmosphere. Also, get no boost noise at all from the symposer. When I get on the car hard the engine response is totally linear like a normally aspirated engine and it is distinctly lacking in power.
 


TyphoonFiST

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#7
Where is the BOV located, front near the intake or at the rear near the turbo? Did take note of more symptoms today. At low speeds on roads with no traffic I can hear a hissing gas release at each gear change, basically a less loud version of boost being vented to atmosphere. At roughly 40 mph in very light traffic I can also hear a very subtle sort of whoosh/hiss that I think may be the boost venting to atmosphere. Also, get no boost noise at all from the symposer. When I get on the car hard the engine response is totally linear like a normally aspirated engine and it is distinctly lacking in power.
It's directly on the Turbo* can't miss it. These cars have a BPV Not a BOV. Btw.

Sent from my SM-S908U1 using Tapatalk
 


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#8
Where is the BOV located, front near the intake or at the rear near the turbo? Did take note of more symptoms today. At low speeds on roads with no traffic I can hear a hissing gas release at each gear change, basically a less loud version of boost being vented to atmosphere. At roughly 40 mph in very light traffic I can also hear a very subtle sort of whoosh/hiss that I think may be the boost venting to atmosphere. Also, get no boost noise at all from the symposer. When I get on the car hard the engine response is totally linear like a normally aspirated engine and it is distinctly lacking in power.
well, before you check that, if you're getting boost but no symposer noise, I would check the symposer. They also are plastic and it's not impossible that it could be leaking. If the BPV is leaking but you still have some boost, that shouldn't affect the symposer I wouldn't think
 


OP
scooter123
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Thread Starter #12
Got under the car last night, all the boost hoses are in place and well tightened. I will grant that the Turbo could have siezed but I never shut the engine off if it's not at idle specifically so I don't starve the Turbo of oil. Another tidbit that indicates that the Turbo is spinning is that my fuel economy for this tankful has been about 3 mpg better than I expected. I have been into the throttle more to the lack of trubocharging and expected this take would run around 33-34 mpg. Filled it up with 399.9 miles on the trip listing and took 11.12 gallons of premium. That works out to 36 mpg, a lot better than expected. BTW this indicates that if there were a no turbo switch for the control computer we could have a high mileage option for saving a bit on long trips. BTW, you don't get that crazy torque hit of the turbo but without it's actually a fairly peppy little engine, probably about what the first edition Mazda Miata was like.

I suspect that the BPV is the problem but it's not a repair part, in Ford's Parts World the Wastegate and BPV are one single assembly. Which means that it will cost Ford more to replace the full assembly. I'll be dropping it off Thursday morning, hopefully it will get finished in just 1 day.

So, should we be starting a pool on how long it will be before a Cam Phaser goes full whacko and runs a valve into a piston and blows up the whole engine? Sad to say I am really losing confidence in this car actually lasting for 5 years.
 


Lays

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#13
Thanks for the warning. It means yet another trip to the dealer for another warranty repair. I'm starting to think I should just bite the bullet and order a Mountune MRX long block. The car only has 33-34K miles on it and so far the drivers rear view mirror mirror had the mechanism fail, the slave cylinder jammed, and now the BOV is leaking.

There's absolutely nothing special about the MRX long block, it just has rods and pistons in it, neither of which are a major fail-point in our engine. The stock sleeves are the major issue, along with headgaskets when you get high up in the power range. Headstuds usually stretch, lifting the head and pushing out the headgasket.
 


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