Hey guys,
So I've been having a few problems with my 07 SS/SC lately:

First, my car quit holding 5th gear about 4-5 months ago, it will grab 5th gear and if you coast will stay in and decelerate, however, as soon as you give a touch of gas it pops right into neutral (my guess is a synchronizer)


Next, a slight squeak when the engine fires up, only heard for a second, but it seems to be doing this on every cold start lately. (timing belt?)


Sometimes when i fire up the car I can hear a ridiculous clacking sound, almost like a diesel engine idling. It usually happens on a cold start as well, but sometimes happens on a warm start or if you pull into a gas station or somewhere you will hear it on occasion. I don't hear it all the time, sometimes the car will idle and sound just fine. Which makes it a pain in the ass to get fixed as when i bring it in for service the mechanic will just say "I didn't hear anything wrong". I've popped the hood and it almost certainly sounds like its coming from the supercharger.


Next, when i get to about 4000rpm on the power band the supercharger whine sounds like a hiss (only noticeable with driver window down). Now I'm not too sure if I'm confusing the sound of my intake sucking, but I don't recall it ever sounding like this.


And last, when accelerating theres an almost grinding sound (don't quite know any other way to describe it) accompanied with the supercharger whine, you can also hear it with very little throttle in first and second gear. Its especially noticeable when accelerating next to another car or under a bridge or anywhere with barriers where the sound bounces off, on an open road in the country I don't notice it.


As a result of one or some of these problems I feel like the car doesn't quite have the 'pep' it once did (don't know if its losing power or torque or both). I got the car off some guy at 30000 km (barely even broken in, now at ~94000) and I seem to remember not being able to use more than half throttle without burning the tires in 1st.

Anyways, any input would be great, I like to take my car into shops with at least having a guess at whats wrong otherwise they tend to do the least amount of work possible. Thanks.

 

the squeek in probably just your belt. carry a spare with you. We have timming chains not belts.

also that clack clack on cold starts is your timming chain tensioner. I just did mine, also the only place i could even FIND one of these was GM dealer ship. $75 bolt, 1 hour its in than out ( if you remove valve cover ) 5 minutes if you just remove old and replace with new one. Ill post my link so you can follow. Its a good idea to do this before it lets go and destroys your motor.

follow this, i got a help from a bunch of good guys with videos. everything you need is in here.
https://www.cobaltss.net/forums/prob...-worst-301922/

And i think its time for a tune up ! Seafoam, spark plugs, air filter, fuel filter, injector cleaner.
thats all i can help with. good luck.

 

Ok thanks man. I had spark plugs changed less than 10000km ago, cleaned my k&n filter about the same time. I use fuel system cleaner fairly regularly too.

And another one that worries me which I forgot to post is a metallic clink sound when starting out in first gear sometimes or when shifting gears, sometimes from the left or right side of the car (I only hear it with windows down)

 

I was amazed at the amount of power i got after replacing my fuel filter.. Just saying, starved for fuel.

 

Alright cool I'll definitely look into that. 1 question with seafoam, you dump 1/3 of the bottle into the gas tank, 1/3 into the engine, and 1/3 into the main vacuum line or brake booster. Whereabouts is the main vacuum line located on our cars? I'm definitely no under the hood specialist and wouldn't want to put it in the wrong spot haha. A picture or vid would help me out.