I am hearing air leaking or escaping under the hood of my 2000 PS 7.3 when the transmission shifts wile accelerating somewhat hard, if I take off slow it does not make the noise. The truck runs fine, it has been doing this for several years, but I just been living with it. It seems to have started after I added a cold air intake. It sounds sorta-like when you shake up a pop bottle and then let the air pressure out with your thumb. Has anybody ever heard of anything like this.

 

its your waist gate, now that you have a cold air and are getting sufficent airflow, it happens when you up shift, or when you take off hard and then get off of it because your boost pressure is dropping.

 

Thanks Lawson....is that typical when adding cold air? And what can I do to correct the problem (if anything)??

 

yes its very typical, when i had my 05 psd it was loud as hell. It reminded me of a rice burner

i tried everything i could to fix it, and i couldn't find anything to stop it but putting the old intake back on

 

I guess my main concern was, is that there was nothing else wrong, and that noise is typical of a cold air intake on a 7.3 Thanks

 

Its not your wastegate you cant hear a wastegate on a 7.3 its turbo surge. Its still a very common thing for a 7.3 my truck did it, my dads truck does it. A Wicked Wheel compressor wheel will get rid of it or an ATS Ported Compressor housing (which is what i went with) will get rid of it

 

It not a wastegate when the you are into it hard and boosting and the truck shifts, its got all this compressed air and then it doesnt need it, so it runs backwards and out of the intake and out the filter. The compressor wheel is spinning one way and the air coming out is going the other way. Its not actually turbo surge, its actually called "turbo bark". Turbo surge is more along the line of when accelerating the turbo flutters, basically there isnt enough exhaust gas to keep it spooling smoothly so it speeds up the slows down speeds up then down etc. Hope this helped

 

All this info you guys are adding to this question is of great help!! THANKS

The one thing that really concerned me, was ware was this air noise coming from, because you can't get it to make the noise unless you are driving it. I even put the rear wheels up on jacks and ran it, but without a load on the engine, it won't do it.

What dose a wicked wheel run aprox. (price). And what do these custom tuns, like Swamps and DI run (price wise).

 

Yep because if its not on the ground there isnt a load on the engine so it wont make much boost. You dont have surge its bark no problem its normal. Ww is about 80 bucks give or take

 

You will never hear a wastegate on a 7.3... its not the wastegate...

Its not surge, its called stall, compressor stall. When your truck shifts the boost that has built up at that RPM is no longer needed. It backs up thru the intake track and makes the compressor wheel stall out... A WW will not stop it, nothing will, it did it stock, but you just could not hear it.

WW will help stop surge, but thats about it.