IC pipes, MAF and BOV

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2016 Mazda3 Hatchback
Does anyone know what kind of pipes these are? I've noticed that even after replacing the WGA the car is still slow to accelerate after hard shifting and will stumble (sometimes stall) when coming to a stop. Having a turbo car before I recognize this as a metered air or BOV problem. If I relocate the MAF after the turbo can I remove the recirc on the BOV? Also where is the best place to locate the MAF, and is there anything else involved in doing this?
 

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Does anyone know what kind of pipes these are? sorry i dont, are you running the SMIC?
I've noticed that even after replacing the WGA the car is still slow to accelerate after hard shifting and will stumble (sometimes stall) when coming to a stop. Having a turbo car before I recognize this as a metered air or BOV problem. so have you checked for boost leaks? cleaned your MAF? theres a lot of other things it could be on these cars, and if youre recirculating and if it sounds like the BOV is venting properly it could be your EGR, IAC, or one of the things mentioned above.
If I relocate the MAF after the turbo can I remove the recirc on the BOV? yes, but thats not going to solve this just yetAlso where is the best place to locate the MAF, and is there anything else involved in doing this? on the cold pipe, about 3" from the throttle body. you have a nice long section of straight pipe to work with, the only thing youd need is something to cut the pipe and some couplers. the MAF diameter is 2.75" but the pipes are either 2.25 or 2.5"
 
It is a FMIC, is there a better way that I could take the picture so that someone could identify what kind of setup it is? I replaced the WGA yesterday. Today I changed tranny fluid, spark plugs and coils and ran seafoam through it. Its driving better now but will still stall when coming to a stop if the BOV opens right before slowing down. It feels faster, but shifting from 1-2 seems slow, the turbo feels like it has to respool, I dont know if this is a fuel issue or what. If I redline it and shift fast it doesnt seem to happen as bad.
 
take a pic of the core from the front. what do the couplers say on them? most likely the wagner kit
 
Its driving better now but will still stall when coming to a stop if the BOV opens right before slowing down. It feels faster, but shifting from 1-2 seems slow, the turbo feels like it has to respool, I dont know if this is a fuel issue or what. If I redline it and shift fast it doesnt seem to happen as bad.
actually i have exactly the issue with the engine bogging after the BOV opens right before you go to neutral. if i go into gear its not an issue. ive always assumed its my EGR but the issue has been better lately... its noticably worse when its extremely cold.
by chance... do you have a remote starter?

and the 1-2 shift is ALWAYS slow unless you get a lightened flywheel. it drives me nuts.
 
actually i have exactly the issue with the engine bogging after the BOV opens right before you go to neutral. if i go into gear its not an issue. ive always assumed its my EGR but the issue has been better lately... its noticably worse when its extremely cold.
by chance... do you have a remote starter?

and the 1-2 shift is ALWAYS slow unless you get a lightened flywheel. it drives me nuts.
That seems strange, I thought a heavier flywheel is better for a turbo.. something about it spooling faster.

I was told by the PO that he recently cleaned the egr, what else about the egr could it be?

Unrelated, I do not have a remote starter, but I would like to get a remote for my car (for doors and alarm). Can I buy a used one and program it, how about ones on ebay?
 
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that its a piece of crap. if youre in ohio, i wouldnt be surprised if it was the issue at all. the more you drive the car in cold weather, the more condensation builds up, and since its uncoated iron, it just rusts and rusts and rusts. look at the CDM EGR, if youve got the scratch, its like 120 and will never go bad due to a built in breather setup.
 
This car is from Florida, and has never been driven in Ohio winter. So I'm not sure if that is the issue at least since it was just cleaned by the PO. What do you think about the couplings from the BOV to the intake. It seems like a very weird way to connect them together, like not from a kit. It is an HKS bov, with a recirculation kit on it.
 
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move your maf that way it gets a constant signal of air passing through it. The reason the car stalls out during nuteral is that the blow off valve has released the air that the maf has just read and has dumpped the fuel into the sytem but the air never gets there. There's a bunch of post's on this topic. People dont like doing this due to the fact that it may damage the maf but I have yet to hear or see any body say any thing I've been running that setup for 2 years and im still good.
 
If your car idles smoothly and evenly then the problem is not the EGR valve. IMHO, The recirc setup is too small in diameter. The air coming back to the intake is too restricted. You have two options: either move the Maf to behind the BOV and vent to atmosphere, which will likely require that you add a BPV so something is recirculating air to the SRI so avoid the "turkey" (many threads showing how to do this) - or, remove your intake, cut off the nipple that the recirc hose currently attaches to and weld on a minimum 1" nipple. If the recirc fitting isn't at least 1" diameter, replace it with one that is. Then connect your BOV to your new SRI nipple using at least 1" hose. Also make sure you have a clean air filter at the end of your SRI. A quick test is to remove the air filter and run without it and see if the problem gets a lot better. Don't leave it that way for long though!!! If the car runs significantly better, then restrictive air flow is the problem. Good luck!
 
this is true, a 1" fitting is the minimum to avoid the turkey, but as long as youre recirculating im not convinced its the root cause of the stalling issues. your best bet would be to relocate the maf. then you can do whatever you want venting-wise, and if it persists, it removes the recirc BOV as the source of the problem.
 
Would having the BOV vent to atmosphere with the MAF where it is at be a problem? I couldnt imagine it being much worse than it is now.. maybe even better for the turbo. Of course I would block off where the recirc line went to after the maf.
 
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Hmmm... today I removed the restricted hose and capped off the intake. Now the BOV vents to atmosphere and it has NOT stalled. There is still a turkey sound though, which seems weird, is that because it is a SSQV bov?
 
Hmmm... today I removed the restricted hose and capped off the intake. Now the BOV vents to atmosphere and it has NOT stalled. There is still a turkey sound though, which seems weird, is that because it is a SSQV bov?[/QUOTE

The turkey is compressor surge. If you still have it then you either need to adjust the BOV to release more pressure or run the dual setup with BOV and BPV. Many people on here run that way and there are several threads showing how they're set up.
 
I backed the spring all the way off of the BOV. So the turkey is bad? Am I going to blow out the turbo? Im assuming its been this way for a long time, since I only recently bought it. I was hoping that the catless midpipe would help with the turkey. Do I _need to do a dual setup for the longevity of the car?
 
I backed the spring all the way off of the BOV. So the turkey is bad? Am I going to blow out the turbo? Im assuming its been this way for a long time, since I only recently bought it. I was hoping that the catless midpipe would help with the turkey. Do I _need to do a dual setup for the longevity of the car?

Compressor surge is definitely not good for the turbo. You are basically trying to force boost pressure back through the turbo backwards. Again, many members have ended up running the BOV and a BPV (stock or Forge, for example) to take the excess pressure back to the intake where it re-enters the turbo properly. That, in conjunction with the BOV usually kills the turkey. But most do end up going to 1" diameter nipples and hose from hotpipe to intake to move more air faster.

Here's a link to a "How To" that I found useful:
http://www.mazdas247.com/forum/showthread.php?t=40956
 
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You need a inch large hole for a BOV or BPV to get rid of the turkey (i was luckly to never had the turkey) But at the same time from what i hear its not a true compression surge, Im to lazy at the moment to find quotes, but it really doesnt matter because that sound should stop if the setup is done correctly.

But the main picture shows a BPV setup.. which it shouldnt cause a stalling issue.
 
its the pressure waves reflecting off the compressor and back out the intake when the TB closes... aka, its technically compressor surge. however, these cars run such low boost and the stock BPV is almost adequate, so it doenst reverse the flow of the turbo or stop it, which is really what youre trying to avoid. in theory, it should be bad for the turbo, but there have been zero turbo failures primairly attributed to the turkey at this point.
 
I was told by someone who used to own a msp that the turkey is just a part of these cars and is not to worry about. Is it at all possible that a freer flowing exhaust (no cats) will cause less surge?
 
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