So I posted a video of this Rattle coming from my engine. This is supposedly a timing chain roller fault. I'm going to the dealer with this next week.
http://www.youtube.com/watch?v=8FSf0-dTFLI

oh yeah, the video is inverted horizontally for some reason


Here are two other threads that reference this problem.

https://www.cobaltss.net/forums/general-cobalt-68/secret-tsb-i-thought-everyone-should-know-about-54519/

https://www.cobaltss.net/forums/problems-service-maintenance-69/engine-rattle-190528/

 

Sounds like your were on the same road path as me before. I tried searching for this problem and couldn't find the answer. I remember year or so gas was like 4.50 a gallon, and it kind of forced me to use regular fuel, but I don't know if that was the cause. So, I was looking up in some fourms saying it might be the tensioner, but again I don't know. All I know is I took it to the dealer and they couldn't figure it out or GM. Because the noise would never happen again everytime I took it to the dealer. So they replaced my entire engine under factory warranty without paying a penny. The noise did go away. So I say good luck to ya. Give me some updates of how the process is going.

 

does the sounds every go away or is it constant?

 

I bought my car on Dec 15, 2006. It didn't start until I put a couple miles into the motor thats when the noise started to rattle. It was very annoying. Sounded like a diesel engine from an old mercedes benz. It goes away every now and then. But, taking to the dealer several times couldn't figure it out and neither could GM. So they replaced the entire motor and never had that noise again.

 

The joys of owning a Cobalt

 

Yup the joys of earning one. The SRT-4 was built stronger than the Cobalt. I keep having dreams of my Cobalt getting wrecked by my SRT-4. How weirder can that get?

 

tensioner garentee..hate to tell ya but ive kicked the **** out of manyy srt4's

 

Well they must be some bad drivers. But, I do agree its the tensioner. Is that a bolt that you get from crateenginedepot.com? SRT-4's have strong engines, but the electrical system really sucks badly. Had the throttle sensor going out twice, which caused my former car to back fire, and rev the rpms without my foot on the gas. I kind of miss my car's power, but not the problems I encountered. I believe the Cobalt has better quality than the SRT-4. I only have 11007 miles on it and barely had problems, except my power steering going out and the engine rattling.

 

No its not constant. It comes and goes.... So so far I can tell the dealership its either the timing chain roller or belt tensioner? I'm taking it to the dealer next week.

 

i got the same rattle in my car. i am heading to the dealer tomorrow to get the tensioner replaced. thats what the tech there said it most likely is./