Si (FIXED) New exhaust... new smoke. Normal?

whoisJSR

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OK first off, I've been stockpiling parts for a little over a month and was waiting for a free weekend to install them all. And yesterday and today I did so. My PRL Catted Downpipe (wrapped in Lava Rock exhaust wrap), my AWE Touring Exhaust, and my PRL Flex Fuel Kit are now on the car, running a Stage 2 TSP Flex Fuel tune. And OMG it's freaking awesome. But you guys already know that Stage 2 is sick, so I won't bother going into it ;)

So I'm not pushing the car hard yet (just in case), but 100 miles in, no warning lights, no signals, no nuffin'. But once it gets up to normal temps, white smoke begins to bellow out of the tailpipe. The oil looks normal, and I wasn't getting any smoke before the install. My car just hit 13k miles today, so I'd be surprised if it were anything bad. FWIW the smoke was also coming out of the engine bay.

Doing some Googling it seems the stuff in exhausts when they manufacture it burn off (and I used a TON of PB Blaster taking the stock one off... like almost an entire can lmao). I'm just being paranoid... I think. Have you guys had similar issues with a new exhaust? Did it go away after a few days?

I can try to get a video if you want. It's... bad. Like, I look in the mirror and can barely see the cars behind me lol. It stinks really bad too haha. Any help is greatly appreciated; thanks in advance :D
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Better hope its not a head gasket. Usually fluids burns off in like 20mins
 

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OK first off, I've been stockpiling parts for a little over a month and was waiting for a free weekend to install them all. And yesterday and today I did so. My PRL Catted Downpipe (wrapped in Lava Rock exhaust wrap), my AWE Touring Exhaust, and my PRL Flex Fuel Kit are now on the car, running a Stage 2 TSP Flex Fuel tune. And OMG it's freaking awesome. But you guys already know that Stage 2 is sick, so I won't bother going into it ;)

So I'm not pushing the car hard yet (just in case), but 100 miles in, no warning lights, no signals, no nuffin'. But once it gets up to normal temps, white smoke begins to bellow out of the tailpipe. The oil looks normal, and I wasn't getting any smoke before the install. My car just hit 13k miles today, so I'd be surprised if it were anything bad. FWIW the smoke was also coming out of the engine bay.

Doing some Googling it seems the stuff in exhausts when they manufacture it burn off (and I used a TON of PB Blaster taking the stock one off... like almost an entire can lmao). I'm just being paranoid... I think. Have you guys had similar issues with a new exhaust? Did it go away after a few days?

I can try to get a video if you want. It's... bad. Like, I look in the mirror and can barely see the cars behind me lol. It stinks really bad too haha. Any help is greatly appreciated; thanks in advance :D
I had smoke coming out after my exhaust install also but it wasn't so heavy that I could barely see cars behind me. Just a little white smoke coming out of my hood for the downpipe and a little from the tail pipe. Mine went away after a few drives.
 
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whoisJSR

whoisJSR

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oh man :cry: now I'm even more paranoid! I'll give it about a week before I panic... in the meantime I'll keep an eye on my coolant and oil to make sure I didn't blow anything.
 

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My past experiences, usually yeah for a bit. Like you said, fluids used, fluids that got onto/into hot pipes (oils, greases, etc) and any gasket materials that are in the exhaust stream burn up a little bit. Yeah, give it that week, then slowly ease into panic. lol

You sure you're not just now noticing any smoking? This up and down ass weather Vegas is having is making me notice it in the mornings or later at night. Not so much during the day. It's been light exhaust smoke, not enough for me to worry about.
 


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It's normal especially if it's cold outside its just vapor thats all and for the smoke in the engine bay it's the heat wrap breaking in
 
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I'm nowhere near as hard on this car as I was on my older cars, but I'm sure I've driven it hard enough to see this before, had it been a blown gasket. Also, this is my 6th car with an exhaust and I've never seen this before with the others... Of course, changing the downpipe, I've never had a high flow cat before. I drove it a bit this afternoon and didn't see any smoke. Weird.

Yeah man, this Vegas weather is weird haha. Still glad to be here where wind is all we get in the winter :p
 
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whoisJSR

whoisJSR

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(side note: anyone that can, the E-85 flex fuel kit + TSP Stage 2 tune is by far the single most effective power jump I've ever felt in a tuned 4-cylinder car, with the exception of a turbo swap or a 75HP shot (I've never felt more than that haha). I don't even recognize my car from Friday when I started the modding... It feels like a WRX or an Evo haha.
 
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whoisJSR

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Ok update: it is still smoking after about 4 days. I've noticed a couple things:
-it only does it bad after the engine is warm
-it only does it after I drive hard, and THEN it only does it when I'm stopped and idling. When I stop, the first 10-15 seconds are normal, and then smoke starts to bellow out from both my exhaust (heavily) and my engine bay (lightly).

I suspect my exhaust is leaking from my downpipe somewhere... But what the heck could cause the car to smoke in the first place? Could the E-85 + tune be the cause? Again, I rarely go over 5000 RPM (and never redline), I rarely go hard and I never do pulls or launches, so I doubt my driving habits did anything (not ruling it out, just saying it's unlikely).

I suspect the gasket between the turbo and downpipe might be the leak... But could that be the cause of the smoke? I mean, I've only got about 150 miles on the new exhaust... There's no way that's still the reason it's smoking this much, right? I won't rule out a head gasket either... But I find it a strange coincidence this started happening with the new exhaust and flex fuel. I sincerely doubt that (my oil and coolant still look normal btw)
 
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whoisJSR

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OK, I've been reading into this for almost an hour now... I think I might know the answer. Call it a hunch, but I think it's a gasket on the downpipe.

-PRL gives gaskets for the downpipe-to-frontpipe connection, but my AWE exhaust did not come with any. The AWE exhaust uses the circular copper gasket. I installed that gasket as well as the one PRL gave me.
-If that doesn't fix it, I suspect the metal gasket between the turbo and downpipe (I sure hope not, but we'll see)

Unfortunately I won't have time to fix it until at the earliest this weekend. I'm fairly confident it's not a major issue... I see no signs at all that there's a blown head gasket, that I'm burning oil or coolant (both levels are full and the fluids look normal), that I have any leaks, and my turbo still spools very nicely ;) my car still drives like a bat out of hell when I want it to, and it doesn't seem to do this when it's cold or anything.

I don't actually understand why this gasket could be the issue, but Google tells me I'm not the first (or the 50th) person to have this exact same issue, and when most people suggested bad turbos, bad head gaskets, etc, the only time anyone fixed it was putting the stock downpipe back on. I apologize for this reading more like a diary than anything else, but (as much as I'd like suggestions on what could be the issue) I'd like to document this for people in the future to fix, should anyone else have this issue :)

(And since I like this community and don't plan on leaving anytime soon, expect updates through to the conclusion of this story. One way or another, I will figure out this issue's cause...)
 


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whoisJSR

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I WAS WRONG!

I figured it out! I'm 99% sure of it!

The bad news: it IS the turbo seals (I think) ... but they're not "blown".

I came across this page: https://www.svtperformance.com/threads/aftermarket-downpipes-causing-smoke.1100422/

from a user, PewterCam, there:
"I've done Tons.. and tons of research and screwing around with my car on the issue and a bunch of posts on another forum about it.

Its not actually the Downpipe or bad turbo seals causing the Smoke. The PCV and oil separator on the car is allowing oil to backup into the turbo at idle which pushes out out of the turbo seal. Even cars with stock DP and stock exhaust have been smoking its just less noticeable because the Cat tends to scrub more of the junk from the exhaust before it makes it to the tailpipe but the Carbon buildup will still be present. Mine from Day 1, totally stock, had an oil smell and tons of carbon on the tailpipe and back of the car. Once I went DP and single 3" exhaust it became much worse and strangely the heat from exhaust was yellowing the paint and twice caused the rear reflector to warp and peel away from the car and left the back of the car covered in even more black spots of carbon crap.

There are various band aids like raising the idle which gives just enough relief in the system to allow oil to drain but eventually it will start to smoke again. I tried all kinds of "fixes" on my car and found the best hands down fix is a UPR Dual Valve Catch can and gutting the PCV valve. You need to gut the PCV and let the UPR DV setup take over the all the PCV duties for it to work properly. On my car not only did this 100% solve all the burning oil, smell, and carbon buildup all over the back of the car but I also have not had any more problems with heat melting the reflector and causing it to peel off the car and I noticed the paint is not yellowing around the exhaust either. Leads me to believe the recall for the excessive under body temps is because of the constant oil burning. Anyway I am curious to get my hands on the revised oil separator from ford and give it shot just to see what they changed and see if there is less oil in the catch can. At this point I drain about 1/4 cup of oil every 1000 miles. Hope this helps!"

TL;DR: Here's my theory: The PRL Downpipe + the AWE catback (which is 3") reduced the backpressure enough that I'm burning oil at idle. I am curious whether or not this could fix my issue. To try and diagnose it, I just went for a short, spirited drive to my nearest Weinerschnitzel for some delicious chili cheese treats, and upon returning home the smoking began again. I gave her just enough idle to clear 1000 RPM and boom! The smoking completely stopped! She was clean and clear!

Now the question is: is this the true issue here? If so, is this fix adequate or dangerous? Can I raise RPM in KTuner to make this a thing I don't have to think about? Do I need to get a catch can and check my PCV valve?
 
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vandalSI

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i seem to recall from my old turbo ek that after i wrapped the downpipe, the exhaust wrap will smoke for a while as it burns off whatever coating is on it. could that be it?

edit: nevermind. i read that the smoking was rpm dependent.
 
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Shouts out to Derek and Corey from TSP! :bow: They hooked it up. Really nice of them to take time to edit the tune for me.

OK, moment of truth. I'm going to reflash my car, take it for a nice little drive with the idle changed, and we'll see if that fixes the issue.

If it does, I think I'm going to purchase a catch can and perform a PCV Valve Delete on my car. If it doesn't...:cry: might have to put my stock downpipe back on and start trying piece-by-piece.

I sincerely doubt my turbo went bad, but who knows at this point? Let's hope my theory is the truth here! Updates to come very soon
 
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whoisJSR

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UPDATE:

 
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whoisJSR

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TL;DR (or watch I suppose) for anyone that has this issue in the future: TIGHTEN YOUR DOWNPIPE BOLTS! IF YOU BREAK ONE I SUGGEST YOU FIX IT! (That didn't happen to me; my top bolt near the valve cover (with the nut) came loose; I didn't use thread lock so I wonder if I just didn't torque it correctly). With my new tune from TSP, my newly-torqued bolts, and a check of everything else (intake, flex fuel kit, and rest of the exhaust) I not only got zero smoke after a 30-minute high-boost drive, I hit a new PB of 26 PSI! (In Las Vegas, I didn't expect to hit that number). THANKS TO COREY AND DEREK FOR HELPING ME OUT! :D
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