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Discussion Starter · #1 · (Edited)
Hey guys i have a 2015 wrx. I just got new exhaust put on last week. Catless J pipe & R400 exhaust. I noticed smoke coming out of my exhaust a couple days ago, now this is mostly when i first turn the car on but once the cars at it’s normal idle level it’s still smoke out of the exhaust. I just want to know is this normal or something i should get checked out ?
 

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At start it's mostly condensation. However a catless exhaust will make it worse. It's not a terrible idea to have a leak down test done to make sure you've not lost a head gasket or anything though.
 

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Discussion Starter · #3 ·
I’m trying to post a pic that i took but it’s not letting me upload for whatever reason. Doesn’t effect the driving or power it’s just something i noticed. I’m coming from mustang so never had that type of issue but then again this is the first time iv installed a full aftermarket exhaust
 

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I have seen some smoke from new exhausts before. I believe it is normal for about a week while the new exhaust burns off the crap on the pipes from being manufactured. Sort of a "break-in" if you will. If this persists past 1-2 weeks I would take XJ's advice. I'm sure everything is fine.

Also, are you tuned? Your car REQUIRES a tune once you replace the J-pipe.
 

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Discussion Starter · #5 ·
I have seen some smoke from new exhausts before. I believe it is normal for about a week while the new exhaust burns off the crap on the pipes from being manufactured. Sort of a "break-in" if you will. If this persists past 1-2 weeks I would take XJ's advice. I'm sure everything is fine.

Also, are you tuned? Your car REQUIRES a tune once you replace the J-pipe.
I think tomorrow or Thursday will officially be one week. So if it’s persist this time next week I’ll try that test just to make sure & yes I’m in stage 2 of my Etune. Hopefully will have it finished up by the weekend
 

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when you go catless you change the backpressure in the exhaust, what happens sometimes now is that oil is leaking thru the turbo seals, you may remedy this with perrin's turbo sump restrictor but i have heard that sometimes that doesnt help either. if you live in a cold climate you should be aware of boostcreep that can happen with catless exhaust systems. anyways, good luck be careful have fun.
 

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Discussion Starter · #7 ·
when you go catless you change the backpressure in the exhaust, what happens sometimes now is that oil is leaking thru the turbo seals, you may remedy this with perrin's turbo sump restrictor but i have heard that sometimes that doesnt help either. if you live in a cold climate you should be aware of boostcreep that can happen with catless exhaust systems. anyways, good luck be careful have fun.
I’m over in Philly we just started summer weather but you could be right . I’ll have to see if it continues to happen
 

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If you aren't tuned then a catalytic less exhaust system isn't a great idea just as mentioned. Is it always black colored smoke? Any white or grayish? Both of those would indicate oil in or at the turbo, or anywhere else it should not be. Throw a cat on it and see what it does. Or my recommendation is to have the gaskets checked for leaking then cat it and call Cobb tuning get an access port for it. Backpressure is a big thing in all cars even more with a turbo sitting there. But I'm no pro.....
 
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