weird s/c noise

**Orange04CompG** · 11-13-2013

so i have a 04 comp g and whenever i push the pedal about 1/2 way down and get to about 3k rpms and the boost gauge is about half way up, the s/c makes a weird variation of its normal whine. its like if youre standing on something thats vibrating hard and you say something your voice sounds kind of shaken up, thats what it sounds like. its really hard to describe. ill try to get a video up in a bit. also when it makes the noise you can feel the car holding back. any ideas what this may be? im stumped.

**TwiztdWun** · 11-13-2013

Worn coupler or needle bearings?

**Orange04CompG** · 11-13-2013

heres a link to the videos. im in a neighborhood so i couldnt go to fast for to long or else my neighbors wouldve gotten mad. you have to listen closely though cause i had to use my phone and my keys were bouncing against the plastic
http://www.youtube.com/watch?v=-Rxg1...ature=youtu.be
http://www.youtube.com/watch?v=a1LKl...ature=youtu.be

**Orange04CompG** · 11-13-2013

and i dont think it would be the coupler because if it were, wouldnt it make the noise at idle too? mine only makes it at higher boost psi and its more of a strange variation of the whine than a rattle that would be caused by the bad coupler

**02NavyBlue** · 11-13-2013

There was a post just like this a few months ago, it was basically a shuddering. I'll try to find it but I can't guarantee it with the search.

**Orange04CompG** · 11-13-2013

yeah a shuddering type sound! thats exactly what it is

**02NavyBlue** · 11-13-2013

The post I failed to find had a video too. He'd floor it, it would accelerate fine until like 3,700 rpm, shudder to 4,500 then accelerate perfect to 5,800 and shift.

**TLSheff** · 11-13-2013

Shuddering could be several things, just out of curiousity when was the last time you did a tune up? and how many miles does your car have?

**Scottydoggs** · 11-13-2013

id say its tune up time. how long since the last one? what plugs did you use when you changed them?

**Orange04CompG** · 11-13-2013

i just changed my plugs like a month and a half ago and its ran great until a couple days ago. the shudder isnt from the engine, its from the s/c. if you watch the videos you can hear it. the car has 138k but most are highway miles

**Orange04CompG** · 11-13-2013

and mine runs fine until about 3500rpm and then the shudder doesnt go away until i take my foot off the gas

**ericspecullaas** · 11-13-2013

sometimes a bad harmonic balancer can cause a rumble in the engine or a bad engine mount. had that happen on a 1973 camaro the motor mounts were the wrong ones. you would end up with a vibration in car at any rpm. but that my 0.02

**Scottydoggs** · 11-13-2013

Originally Posted by Orange04CompG

i just changed my plugs like a month and a half ago and its ran great until a couple days ago. the shudder isnt from the engine, its from the s/c. if you watch the videos you can hear it. the car has 138k but most are highway miles

thats totally your engine shuddering, its just that you can hear the engine via the sc as it shudders. and thats what car with misfires sounds like btw.

what plugs did you put in?

**Orange04CompG** · 11-13-2013

iridium tipped ac delco plugs

**Orange04CompG** · 11-13-2013

so what should i start with looking in to?

**Scottydoggs** · 11-13-2013

pull the plugs, check them out. check the wires to see they are not stuck to the exhaust manifolds or something like that. or a cracked coil.

**Orange04CompG** · 11-13-2013

my coils and wires are good. ill pull the plugs tomorrow. anything else i should check?

**TLSheff** · 11-14-2013

It is an 04 model... with the craptastic LIM gaskets... are you low on coolant?

**Orange04CompG** · 11-14-2013

Nope. All my fluids are good. This morning it got worse though. It's definitely the engine shuddering. You can feel it through the gas pedal when you step on it. I'm going to replace my engine mounts with the poly ones from zzp and check my plugs and if that doesn't fix it I'm taking it somewhere to get it looked at. I love my car with a passion but these repair bills are killing me lol