So I have seen multiple posts about clicking noises coming from the engine but I have not seen any that were doing what mine is. I have an 06 Cobalt SS/SC with 117km and when the engine is cold and idling it makes this constant clicking noise. When the engine warms up it goes away completely.

I have read horror storys about timing chains and people having to replace the whole timing chain system because of poor rollers or they had their engines just blow.

I guess I am just wondering if anyone has had this issue. Could it be a lifter issue? I am having my mechanic take a look at it in like a week because I am 70 miles away at college and cant make it back any sooner but I would like an idea of what I am dealing with here.

 

Post a video if possible.

 

I added it as an attachment.

 

Oh the sounds I'm hearing in that video... So much more than a clicking. Sounds like a rod knocking too, or maybe it's just me.

 

The thing is when it warms up the noise goes away completely... And even when it does make the noise I can't notice anything performance wise that is wrong. Its just the awful noise.... Because it goes away when warm I was thinking lifter issues.

 

Just started the car for the first time today. Engine temp was 40 degrees F and there was no noise so I guess it isn't temp related. Drove it for a little and there wasnt any issues. I just hope it makes the noise when I bring it to the shop.

 

Switch oil. Mine did that on Mobile 1. I run Pennzoil Platinum and the noise went away. My description is similar. There was a clicking or tapping when the engine was cold and it was close to freezing temp out. Otherwise, everything seemed fine. And the noise went away after the engine warmed up. That was 2 years ago.

 

Well my mechanic took a look at it and admitted that he typically is a transmission guy but at first I could not get to car to make the sound. I left to car with him for about a week and he started and drove it off and on. He said he got it to make that awful sound once but it went away shortly after. He called other local shops and dealers and they were stumped too. He suggested I change the oil and just run it because it is not worth ripping the engine apart if he does not really know what it is. If it starts doing it constantly then it will go in. But he replaced the thermostat and did wheel bearings so that hurt my wallet a little...

 

Maybe ur timing chain tensioner is toast and or not getting oil till it's warm and thinner, could be chain slapping around. What thickness of oil u use? 5w30?

 

I run Mobile 1 5w-30 extended miles. Mechanic does not think it is timing chain. but who knows.

 

Unless your mechanic has worked specifically on these car/engine a lot then I would say he is right. Some of these guys have torn there engine apart probably more than your mechanic has even worked on them.

I would check to see if you have the upgraded tensioner, Also my 2 cents it says mobil 1 on the oil cap for a reason and it isn't marketing cuz that is a terrible spot and mobil 1 doesn't really need it to be honest.

It does sound like rod knock or a spun bearing, Possibly a very terrible idle. But it is a video and they don't do the best justice.

Lastly I would grab a solid handled screw driver or go buy a stethoscope, Then try to pin point the area you are hearing the noise from and go from there.

Hope this helps, Keep us posted.

 

So I have been checking out other forums and I am now convinced that is due to the fact that I do NOT have the upgraded timing chain tensioner. Now here is the golden question.... Do I replace the tensioner myself or bring it to my local chevy dealer. If I do take it to my local dealer does anyone know how much it is going to cost me?

Note that I have never really worked on car engines, I usually work on snowmobiles and cars aren't my expertise.

 

I did mine myself just tore the valve cover off and zip tied the chain to the cam gears for extra safety

 

Im going to see what the dealer says for a quote on replacing it. No point in risking me replacing it and having it skip a tooth and destroying my motor. If the quote is ridiculous I will do it myself.

 

I'm was a first timer and did it, there isn't much risk of skipping a tooth, if it's not tensioning and it hasn't skipped it won't do it when u change it. The only scary part is releasing the tensioner when it's preloaded in the motor. Wondering it u sprung it right or not.

 

Alright so the stealership will not even get back to me with a quote and I am getting nervous driving my car so I decided that I am going to do this job myself. Now the only thing I am confused about with this job is what tensioner to buy... And do you need to smack every tensioner to have it set or just the older style ones. Everyone says something different. This is the tensioner I am looking at getting Any thoughts?

 

That's the right one it looks like, but why not save money and go here

Timing Chain Tensioner Assembly - Camshafts & Valvetrain

Yes u have to smack Them. It's just a light quick smack. If ur unsure, put it in, don't tighten, give it a smack and take it out to see if u did it right. So u know how to do it

 

I just did my entire timing set on my LNF, 20 hours roughly. That's including like 3 meals and breaks so probably closer to 15 hours. You should check on the black chain guide. Just remove the hex bolt on the cam side of the motor near the engine hoist point. My chain guide was broke.

 

How difficult is it to do the entire assembly? I am worried I am going to have broke guides when I pull mine apart....

 

20hrs, including 3 meals, breaks, and googling TQ specs for bolts I forgot about. Probably closer to 12 if you have it all already.

 

Alright I did it! Tore off the valve cover and replaced the timing chain tensioner! Took me about 3 hours but it was pretty easy!

Here's a helpful trick I picked up; When you install the new tensioner and whack it to get it to engage there is still slack in the chain. I personally didnt wanna start my car with this slack being present. So I put my car in 5th gear and pushed it forward maybe 6 inches and the chain snapped right into place! No more worries about whether it engaged or not!

 

Your chain guides all look to be in ok condition? The black gude is usually the first to break.

 

As far as I could tell, all looked well.

 

I did have one issue today though... I have put about a little over 100 miles on the car since installing the tensioner with no issues. Then I pulled out of a parking lot into traffic and had to accelerate hard and right after my check engine light came on and I got a p0017 code. Which is Cam shaft position. I had it reset and drove it about 5 miles without it coming back on.... I guess I just wait and hope that I dont pull that code again... A little nervous. Any thoughts? If it was out of position I would keep pulling that code consistantly right?

 

Alright so here is the conclusion to this post... It isnt pretty either...
I replaced the timing chain tensioner correctly and drove the car without an issue for about 150 miles before getting a p0017 code. The code went away then came back so I took it in to the dealer. Dealer told me that the whole timing assembly was shot and needed to be replaced. I talked to the mechanic and he said it looks like someone went in and tried to replaced the whole assembly on their own (Must have been previous owner of the car) and did not tighten everything properly so that was why the car was making the noise. Long story short I got it replaced and it cost me a little over $1400 if I remember right... The end.