So I just installed my new PCM V1.0 in my Monte and wow I like the changes! Best way I can describe it is you know when ur car runs really well when its kinda cold out seems like this PCM makes it run like that all the time. ANYWAYS under hard acceleration (Getting on the freeway on-ramp) I hear a rattling I can't tell but almost sounds like its coming from under my car. (Sounds like a bunch of marbles rattling around.) Anyone have any ideas to what it is?

 

Taking a guess and saying wheel bearings.

 

need to determine if you hear this noise under any other condition (in park, in neutral, going straight, turning, etc etc) what kind of rattle/noise is it? (yes i know that's somewhat subjective)

 

I don't hear it when parked or going slow or taking it easy on the gas. I know its nothing with the wheels I just had all of that checked and I was thinking something with the cat or exhaust. It only happens when I am really punching it going straight. I have a new down pipe coming tomorrow so I guess that will rule one thing out when I get that put on.

 

Do you have a K&N intake?

A lot of time the filter comes loose and I can hear the metal on the filter hitting my PCM, all I do it pop the hood, tighten up the connector on the filter and it stops.

Scared the hell out of me the first time I heard it.

 

So I checked all those things and I noticed when I was replacing my belt that the A/C condenser wheel seems to rattle a little. Is this normal. In putting the belt on I tapped the front side of the wheel and it seems like rattle a little bit. I was thinking that might be my problem but I am having no troubles with my A/C at all except for losing a lil power when its on lol.

 

You're sure it's not wheel bearings?

 

Or the last mechanic that worked on the car? Trapped underneith. lol

 

Did you put a downpipe on? Maybe that is rattling or a heat shield?

 

I don't have the downpipe on yet but I am hoping when I do that will eliminate one option as to what is might be. This rattle is not effecting the car at this point but I don't wanna find out down the road its something bad. I guess I will get the downpipe installed and have them check the resonator and go from there.