so i put in my new intake the other day and it went smoothly, minus me accidentally putting the maf back in the wrong way round. I freaked when the car at idle was bouncing between 840 rpm and 1000 rmp. but anyway with that fixed, it runs smooth again. I have a forge 007 dv in with the unpainted spring inside it. i can finally hear it now! But that is where my question comes in. When the dv releases air it makes a pfff noise. but when I am driving, it sounds like there is a long pfffffffff noise untill i let off the throttle and hear the pff noise of the release of the dv. I am not sure if this noise is a bad cat, my turbo, or the dv. it is a 98 1.8tm. i can probably get a sound clip for you guys and some pictures if it would help.

Thanks in advance,
miles

 

While you have the throttle all the way open you shouldn't hear air releasing, only turbo whistle. When the throttle ISN'T all the way open you will hear air releasing.

 

yea under normal non WOT driving youll hear some air releasing and also air from the intake you put in.. but under full throttle it should be alllll turbo til you shift or let off the pedal

 

he might be hearing air building up

 

I bet the spring in the DV is too soft and under full boost the DV vents a little.

 

that is exactly what i was thinking. i looked in there today and noticed that i had forgotten to tighten my hose clamp on the filter side of the MAF, i tightened it but I am hearing the same noise still. would it harm my engine if I tried a harder spring?

 

it can harm your turbo if you put in a spring that is too heavy by making the turbo back spin when you let off the gas, so try one spring up from what you have and see if that helps.

 

how will i know if the spring up from the one i am currently running is working how it is supposed to?

 

A boost gauge would be the best. If you are tight for funds, you can listen for turbo flutter. If its fluttering then its too tight, or when your wot and you can hear air escape then its to soft. You can either put in a new spring to tighten it up or if you only have one spring then you can go to ace or any other hardware store and put some washers in to stiffen in up. Long as its not fluttering then you wont be hurting the turbo though

 

the fluttering is not what hurts the turbo the most, the dv not opening correctly is what really hurts it, so just make sure its not too heavy or soft. This is why I love my forge splitter, it has an adjustment ring, which lets you dial in the perfect spring tension.