(Long Read)
Ok, I have had this issue for quite a while now, and cant figure out what it is!

lil history: the car was reading "lean" as hell on the WB, so I went looking to see if there was a leak. What I could find w/ my "un-experienced" eyes/ears was a loud "whistle" coming from under the ex. mani. It ONLY whistles on "Cold Starts". (Works 70mm DP)

I took it to shop (A), and was told my dp was possibly leaking. He took out the spacer, and told me "I dont know why this (spacer) is even there"! So he took out the spacer. I go home thinking (hoping) this was the issue, but I let the car cool down a bit, and re-started it, and I still have a whistle!

I went to another shop, and was told that he used a stethascope to listen for any audible changes, and there was a huge leak coming from my DP. Cause not only was the spacer taken out, but apprently there was another reg. gasket that was supposed to go w/ the donut gasket, that was gone...
So I purchase the "kit" from Works for the DP. A week later I go back to the shop, to 1. re-weld my WB bung on the DP w/ TIG welds, replace the spacer/donut gasket, reg. gasket, and bolts.

At this point my WB is now reading perfectly, the car feels a lil different "tighter" throttle response, which would lead me to believe that the issue was fixed... Unfortuneately for me, my car is still whistling! I obviously had a leak there as well, and is now fixed, but where the fk is this whistle coming from??? I was told that everything should be good to go, no leaks anywhere... I was told that the next thing to check is the "timing belt"... Has any1 had a noisy timing belt, and what was the sound like?

Question: @ shop A, they pressurized my valve cover/motor when doing a boost leak test, by forgetting to take off the hose to the valve cover. Oil/steam came out of the oil cap (twice)! My question is could this have caused any damage, possibly lifting the head? Is it even possible the whistle could be coming from the heads? Im at my witts end here! I have been to 2 shops, twice a piece, just for this issue, and dont know what else to do... And yes, they were evo specific shops...

Has any1 ever had a whistle? Where and what was the fix?

TIA

 

Make sure your PCV valve is connected onto your valve cover. Check all your vacuum lines as one may have blown off. Especially around your FPR since that could cause your car to seriously lean out. Theres no way running that pressure test would have lifted your head. And even it it did you would have a leaky headgasket and your coolant and oil would mix. You wouldnt just hear a whistle.

 

it might be coming from the butterfly valve in your throttle body, some seals in the throttle body may be leaking...

 

I checked the PCV valve, thats fine... Im a newb when it comes to "DIY" around my engine bay, but learning. Not exactly sure where all of the vacuum lines are located, but I would hope that the guys at the shop would have looked... Can you give me a brief description of where to start? TIA

Johnboy: It doesnt sound like its coming from the TB, but I will check it again, when I leave work. It sounds like its still coming from under the ex. mani...

thanks for the input fellas

 

Maybe a leak at the outlet of the turbo (jpipe/licp connections) or leaking boost control lines.

 

Not unless they leak tested well over 1000psi. Now if loads of oil was pushed into the chamber it can knock bad enough to lift the head

 

My guess is the turbo outlet pipe also.

 

I get a slight whistle sound at low RPMs on occasion. It's not a constant thing. It's a VERY very quiet noise. It goes up with the revs. I've traced it to be near the serp belt. Never found out what it was. Happens once in a great while and it's been doing this for over a year. Nothing is odd except for this noise on occasion. Drives the same, idles the same, boost gauges reads the same at idles as it always has, etc. I decided that if it is something, once it fails, then, maybe I'll care. But for now, I could care less.

Does the car leak boost visably on the boost gauge? Try another boost leak test. If the whistle goes up and down with engine RPMs, I doubt it is a boost/vaccum leak of any kind.

 

could this be a bad PCV valve? just asking!

 

Yep, I was going to say this also since it happened recently to me!

 

thanks for the input fellas!

I have had the car leak tested, in Jan. and was fine. Logging, the car is holding boost just fine. I just noticed, that after the dp leak was fixed, Im now hittim ~ 3 psi more, and earlier, (~ 2750-3000) in 3rd, and wasnt even dialed in yet. And even more in 4th! So its holding boost. Had the pcv valve looked at and was fine. I check that from time to time, to see if its leaking...

I have been wondering why my boost was so low compared to others during spool up... It should be interesting to see how fast I can get her to spool now, once dialed in, and this damn leak is fixed, of course...

I'll have to get back to a shop and have them specifically look @ the outlet of the turbo (jpipe/licp connections) as recommended. I remember when I had the LICP installed (Injen), it was fitting perfectly, so a lil elbow grease was used, maybe this is the culprit...