Recently my procharger has started to make a new noise. It is not the constant whistle, more like a rattle for lack of words. I was checking out another forum and ran across this video of an 03/04 cobra with a Kenne Bell and it sounded similar to my procharger. Like I said, it sounds similar, but not nearly as loud.

Here's the video and you will hear it about half way through when they go to the under hood shot.

Click here to see Video

Anybody know what may be causing this sound? I don't know much, but I am assuming it needs rebuilt. Any help is appreciated.

 

that guys car must have something seriously wrong, but i wouldnt think that it would be easy to compare a sound coming from a messed up twin screw to a messed up centri blower. geting it rebuilt couldnt hurt.

 

that was a nice car btw lol

 

Have you checked the oil in your Porcharger? Just ruling out stuff.

 

I understand a twin screw and centri blower aren't the same, but the sound was similar.

I checked the oil a little while back, but I will go check again.

 

The noise is caused by irratic idle speed. The noise should be gone as soon as you bring it up to 900 rpm. At idle the motor pulsates(for lack of a better term) causing the impellers to jerk back and forth enough to make the noise. I did a 96 Cobra ATI Procharger kit and it made the same noise until we had the ECM reflashed and brought the idle speed up to about 800-900rpm so the motor was smoothier and the noise was gone. On the ati it is the gears rattling inside it from the irratic belt speeds at idle.

 

I have had it on for 3-4 months now and it has just recently started this. It was a used unit if that makes a difference. Would putting a new belt possibly solve this? I don't know how old the kit/belt is and that would be the cheapest route. Also from the looks of it, I think I need two new idlers. Only thing I hate about that, its about $90 a piece for them.

 

It may only be what DanvillePerformance said but when the bearings went in my Vortech, thats also how it sounded. I would bypass the s/c pulley to be positive that's the source of the noise. Is it slightly oily around the bearings and getting worse? That's another indication of bearing wear. You wouldn't feel anything if you wiggle the pulley until it's way beyond worn. Make sure it has enough oil and isn't leaking and you're probably ok. Oh and make sure the pulley bolts haven't loosened and letting the pulleys move.

 

sounds like a bad bearing to me. best way to describe it is like there is rocks in there at idle

 

Doubtful it's the bearings...would be making much more racket if that was the case. It's either 2 things...gear backlash or cavitation. Backlash is mostly the case with a new head unit as it hasn't broken in yet...takes a few thousand miles really and then it quietens down. Cavitation is caused by air bubbles, for lack of a better description, and sounds like marbles rattling around. If it goes away with just a little bit of throttle then don't worry about it. Also check your belt tension....should be very tight.