[SleeperQ]

I own a 2018 q50 lux with a new 40k on her.
The car isn't clicking or knocking. The exhaust seemed very loud. Brought her back to the dealer. Not infinti... Said they did something with the flanges. They denied the issue until I said. Use a smoke test and find it. You don't have it ? Okay let me grab some dish soap and water and spray it on for you morons. I left there happier because the car was much quieter after. The sound was coming out of the pipes more like 80 percent rather than where the downpipes meet my cat. It's not crazy loud. It's just when I drive it. It has a bit of a loud growl where the engine is shifting into higher gears, normal, but to what noise decibel? How deep of a growl SHOULD it be. No acceleration problems. when revved in place it sounds like it's still pushing out air from the back of motor. Not a put put. Just sounds like air/exhaust leaking. Or maybe that's just how loud the cars are made... Going to have to take her to my trusted mech. I'll put a brand new high end conservative sounding after market cat back on her in the spring replace the down pipes or whatever it is if it's even there. I can post audio. But untill then. Has anyone had a similar issue with there q? I'm in the salt belt so oil based under coats and washes. But it's only seen 2 winters and was from down south prior. Very little under rust. I love the car. I wish I had a brand new one next to me to compare sound. Just sounds like exhaust or air coming from back of engine where the manifold would be or down pipes. But it's not the manifold based on the noise it's making. Which again is just a little loud. I think if I drop the entire exhaust this thing would sound amazing. Still low key and I wouldn't be hearing like air or exhaust noise coming from that wheel well. Right in front of my dash area. Any comments or shared experiences with stock exhausts and similar problems would be much appreciated. Or if I'm just looking for problems because I'm hyper focused on it. Any advisement is welcomed ! Thanks

 

[SleeperQ]

That tracks. Thanks

 

[SleeperQ]

If it sounds like it’s coming from a wheel well area, and the dealership already claims to have tightened something, I’d guess the gasket between the upper and lower cats is misaligned at best, or just plain missing at worst.

Hey Skyline, excellent point. misalignment based on the Just escaping air sound. I thought I could be hearing my turbos. The cars just.... loud. Not bad sounding. If that's the way the car sounds okay! Sounds like a sports car. I have my doubts.
I don't think that There's any true way to find out without a mechanic, smoke machine ect. Because better as it sits; It's still there. Something is causing excessive noise.
Them under or over/under torqueing the flanges on my exhaust sounds like something they very well could have done. Not aligned even at that , them just trying to briefly appease someone and not go out of there way to find the problem,
The entire exhaust probably needs to be gone over. Gaskets replaced. Maybe a pinhole on a tiny rust prone spot that made a hole.. I really want to rip the old off and attach aftermarket conservative high quality, cat back to last her life.
As the temp drops and the rubber gaskets expand and contract. It's going to exasperate any problem of course. That car doesn't like to run from cold starts.
I can't be alone in the exhaust leak boat over here.
Your advisement/ Opinion is much appreciated skyline. Thanks for the input.

 

[SleeperQ]

Sleeper,,I read what you wrote,,it seemed like it poured from your mind onto the page,and I got a good understanding of your situation and I'm pretty clear on your concerns. Not sure how your format required guidance or corrections,,just a thought..Perhaps I'm same as you? Good luck..

Haha well there's always people that like to point out redundant crap like formatting. I'm doing this at work half the time lol 🤣 don't worry I'll remember to indent next time.
That's just my creative process I guess. Mind to thumb. Lol.
Any advisement or ideas welcomed. Even if it's a shot in the dark.

 

[SleeperQ]

So you know the exhaust gaskets are metal, not rubber. Turbo cars produce way too much heat to use any other material in their exhaust system.

I’d say put a video up when you can so all can hear it. You’ll get a lot more engagement that way. And Honestly, it’s all speculation until you do. Your car’s previous owner count is what makes me think it’s a misaligned gasket. I’m betting the previous owner had down pipes and swapped back to the secondary cats before trading up so they can either transfer or sell the down pipes.
[/QUOTE
Understood. Appreciate the feedback a lot! and again, new to this.
No I've never owned a vehicle that is as advanced as this. In past I've purchased privately. Older cars from 1k to 5k bucks and repaired them myself (most things non engine related) then drive them till the wheels fall off. I'm mechanically inclined but not a mechanic by trade. So I'm completely new and unfamiliar with how these engines run. And I have zero point of reference. What you say makes sense though. They probably did as the car came pre tinted and smoked wheels Plasti dipped all that jazz. It was someones baby. It wouldn't surprise me if that's exactly what happened because I wanna swap em out!. But as you said its all speculation until I upload a video. I'm becoming more used to the vehicle each day. I'll post a video of the car at idle and when driving. Its loudest when I'm between 15 and 40mph and transmission is shifting up. Quiet as a church mouse on highway and idle. Maybe I'm just being hyper sensitive because the last thing I need problems on a newly purchased relatively young vehicle. I'll upload some videos tonight.
Thanks you for all the help

 

[SleeperQ]

No worries! If you want some ideas for mods, my most recent video was on getting started with the VR30

https://m.youtube.com/@pitcrewnation1170?itct=CDsQoTAYACITCPyspsSfw_sCFS-Z5QcdkLYGjg%3D%3D

Absolutely I'm looking at laying out a plan to swap out exhaust and intake and intercooler. Any advisement is much appreciated. Send me the link. I just uploaded a video to YouTube that's rough cut but should be able to push past the text wall speculation.

 

[SleeperQ]

Here's a very roughly edited cut of some of the noises that are coming from my car which can seem almost nonexistent at times and other times obnoxious depending on where the mic is picking it up. My speed. Shifting ect. Revving in park gently. Two locations.
in response to @SkylineDreamz thanks for your advisement Thus far.

 

[SleeperQ]

Here's a very roughly edited cut of some of the noises that are coming from my car which can seem almost nonexistent at times and other times obnoxious depending on where the mic is picking it up. My speed. Shifting ect. Revving in park gently. Two locations.
in response to @SkylineDreamz thanks for your advisement Thus far.

Wait till you hear under car

 

[SleeperQ]

Absolutely I'm looking at laying out a plan to swap out exhaust and intake and intercooler. Any advisement is much appreciated. Send me the link. I just uploaded a video to YouTube that's rough cut but should be able to push past the text wall speculation.

Got it. Pardon. I'm a noob with forums bro

Sounds like it could be two things at once; a misaligned exhaust gasket, and it sounds like the lower cat isn’t bolted to its hanger and it’s slapping around in there. I would take it to a muffler shop and ask them if they would inspect it and show you what they find. If it’s cheap enough, have them fix it. If it’s not a cheap repair, video an inspection with the muffler shop and go back to the dealer with that video and tell them they need to actually fix it, and quit wasting your time.

Really appreciate your advisement. Skyline. That is exactly what I'm going to do. The dealership should fix it properly. Was only purchased a month ago but I believe it had a 30 or 60 day warranty if there was something wrong. They should have to make it right. But who knows if they'll honor it. This is why id rather take it to my trusted mechanic who's gonna tell it like it is. You've given me some information to work with I'll continue to post updates on it. Again, very much appreciated insight.

 

[SleeperQ]

Somehow speed clicked and accidentally ended up on your “music” folder, you’ve got a wide range LOL.

From bach to Tupac all music across all decades and genres welcome hahaha 🤣

 

[SleeperQ]

Sounds like it could be two things at once; a misaligned exhaust gasket, and it sounds like the lower cat isn’t bolted to its hanger and it’s slapping around in there. I would take it to a muffler shop and ask them if they would inspect it and show you what they find. If it’s cheap enough, have them fix it. If it’s not a cheap repair, video an inspection with the muffler shop and go back to the dealer with that video and tell them they need to actually fix it, and quit wasting your time.

You called it Skyline. Misaligned. That was fixed. My trusted mechanic got me under the car. Oh boy well. Almost zero rust. But the boys in the shop found an aftermarket cat back. 3 inch pipes from my cat. should have realized and compared them to an average car. They look twice the size. (I thought it was a chrome pipe beauty cover) Not bad sounding.
if there was anything that could have done. he would have. Aside from the realigning. The car is just aggressive. Loud wide pipes. My mechanic thought it sounded good at first from afar. Little black on some cat back joints. To be expected. Well now I know there not just exhaust covers but my pipes. My mistake for not looking closer. That's just the cars voice. Previous owner did a decent job on the mod. Think tomorrow I'll check to see if there's an aftermarket intercooler in it LOL what luck would that be. Intake seems stock, the turbos keep the O2 flowing. Happy I have some resolution with this issue. It's a really nice car. Thanks for all your help. Let me know if you have any tune tips that won't blow up the engine.
Rw

 

[SleeperQ]

Good to hear you had a great resolution to this. 3” exhaust setups aren’t cheap, so that’s a big up!!

tune tips as in what tuner do people recommend? Or are you a DIYer that wants to know the safe limits so you don’t demolish your new car?

Pardon, been buried. Tis the season. Yeah I'll take the win on that on aftermarket C.A.T back.
In response; the later. Im not someone wanting to throw off the cars computers. Or destroy my vehicle by over modding/improperly. DiY guy. Possibly with the help of a professional friend with shop depending on what it is.
Safe limits. Smart mods that help the cars performance. I'm not looking to be that guy who's snapping belts and destroying their transmission. Any advisement welcomed and appreciated !