edit: after investigating it seems like it's wastegate flutter due to tune or wastegate not holding pressure.

its basically caused when car is in high gear and low boost. I.e 5th gear 60mph, accelerate a little and let of the gas the noise starts.

If i boost proprerly going into 5th gear it's fine no noise.

Taking it it to another shop, hoping they might be able to figure it out.

had people tell the grimspeed 3 port could cause it as well and to get a Manuel boost controller.


Or since im running an open dump downpipe I'm going to hear all sorts of weird noises.
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To the point, car makes a weird noise as if something is hitting underneath the passenger side.

Nosie started after ets testpipe and map external dump downpipe install.

nosie only occurs After wot and the car is crushing above 50mph. When u step on the gas it goes away and when you're cruise below 50 it goes away.

two shops took a look at it, one said the external dump pipe from the downpipe is hitting the body of the car. When checked for clearance there's about a less than inch gap. So can it be hitting the body under wot because the engine moves back?

The second shop said it could be wastegate flutter. Both shops took a ride in the car and heard the noise.

heres a video maybe someone can shine some light on it.

https://youtu.be/_TESYrQybsY

 

Is it like a scraping noise? when cruising the sound is present but as soon as you step on the gas it goes away? and often you may hear the noise under certain rpm?
Post the Link as well...

 

link is up check it out you'll get a better idea than I can explain.

 

Check the under tray if you have one. Also see if the downpipe is making contact with the firewall, its a pretty tight clearance.

 

nothing loose or anything it's coming from the open dump pipe

 

IMO you need a better tuner than you have available. Hit up wtftuned and get a proper e-tune that will work fine with what you're running. I have a 3port and a proper tune and it has zero issues and been running it for 30k now.

 

yea im starting to think it is my tune.