2006 GTI freight train whistling noise at WOT

[5aprilc]

Hi everyone,

I was just curious if anyone could point me in the right direction for curing this problem. A friend of mine thinks my aftermarket cat back exhaust is the cause of the noise, but I wasn't so sure. The only other mods that I've done to the car is a stage 1 APR tune, and a Rev D diverter valve. Also, the car doesn't feel like it's leaking boost and I haven't noticed any power loss.

Thank you,

Charlie

 

[Das Gespenst]

Do you have a boost gauge? Also what ca5back do you have and how long has it been on?

 

[5aprilc]

I have a boost gauge, it just hasn't been installed yet. I'll be doing that this weekend. I just bought a cheap Manzo cat back exhaust like two years ago. I believe the piping diameter is 2.25".

 

[Das Gespenst]

I have a boost gauge, it just hasn't been installed yet. I'll be doing that this weekend. I just bought a cheap Manzo cat back exhaust like two years ago. I believe the piping diameter is 2.25".

Get that gauge installed and report back. If it's a boost leak you should see it on the gauge. For now, Jack the car up and check all the joints on your exhaust. If there's a leak somewhere you should see soot deposits where it's coming out.

 

[707Stang]

I was gonna suggest the possibility of the PCV being faulty. I have seen some that do that back in the day. not as common as a total failure

 

[5aprilc]

I was gonna suggest the possibility of the PCV being faulty. I have seen some that do that back in the day. not as common as a total failure

So you've seen it when a faulty PCV valve makes noise at WOT?

 

[GTICT07]

Its an exhaust horn. The kid I got my car from had it installed. WOT around 4000 rpm. Annoying. not sure how to remove it. I thought I was the only one

 

[GTICT07]

Exhaust horn in the exaust. it sounds like a train at WOT

 

[5aprilc]

Are you serious? I wonder if it will go away once I remove the stock downpipe?

 

[inverse_square]

Seems like A LOT of work to put it in the DP. My guess is that it is not in the DP, but somewhere much easier to get to.

 

[5aprilc]

I changed out the stock cat back with a Manzo exhaust. I wonder if they install those horns in their systems?

 

[5aprilc]

I just hope it's not the PCV valve whining.

 

[larcic]

i doubt its in the dp and if u replaced ur exhaust already its not there. didnt u also recently replace your pcv? have you checked the rest of ur charge pipes for oil on the outside of them to find a leak? install the gauge asap, takes less than 30 minutes if you follow my diy. i didnt remove anything not even the battery

 

[5aprilc]

I never replaced the stock PCV. I didn't see any oil on the pipes when I was removing the noise pipe. But I didn't really look that close. I need to buy a new gauge, I ended up returning the eBay one that I purchased.

 

[larcic]

any stock pcv system or blockoff will have oil in the charge pipes due to the rear port. the reason you didnt find much or any in the noise pipe is because its post intercooler and pre front pcv port. only a catchcan will reduce oil in your charge pipes. it is possible that your pcv went. check it with the dipstick to see if your idle changes. is there oil coming out of your oil cap? get the newsouth if mechanical. get the awe for digital. use a inline fuel filter for both in the line. specially since you are keeping stock pcv. you dont want to cheap out on the boost gauge. I found out cheap ones or dirty ones(oil) are very inaccurate.