Noisey at Idle

[dmac1274]

At idle when this car warms up it sounds like its going to rattle itself apart in the engine bay.

I went back to the dealer and he said "they all do that." True to his word we went out and started another one on the lot and once it warmed up the same ticking and rattling from the top of the engine set in.

This is the very first "small turbo" engine I have owned. I know if I heard this kind of noise coming from my truck I would think the lifters were about to fall off.

Am I just paranoid?

TIA if you can ease my worries or get me headed in the right direction for a fix.

Off idle nearly all of the noise goes away but man sitting at a stop light is almost embarassing.

DMac

 

[opsethb]

Mine isn't that lound and does not always make the noise, but I do hear it. I think its because the stock car has almost no exhaust noise so you the valvetrain noise stands out. It might have something to do with the variable timing as well as it seems to come and go.

 

[SSpeckerwood]

i think its since most of the small engines have timing belts and not timing chains like the sonic has. that makes them alot quieter. with it having the chain you'll get more motor noise

 

[domduduman]

Rattling Sound

I am having the same noise issue with my Sonic. I took it to one dealer and they said there's nothing wrong with it. I took it to another and they said there is definitely something wrong with the noise. Anyway, I'll update what I find out in the next day or so.

 

[SooperSonic]

How many miles do you have on the engine? My engine made a light rattling noise during the break in but it's not noticeable anymore. I'm a little over 2500 miles now.

If it doesn't go away I would contact the dealer again

 

[Ubryaj]

Mine has made a rattle at idle since new. It goes away when I'm driving and haven't had time to take it to the dealer. My rattle seems to be coming from the passenger side of the dash. I planned to stick my head under the dash and look around when I get some time.

 

[Eric Smit]

Mine still makes it and it's OVER 9000 miles later.


-Eric Smit

 

[SooperSonic]

Maybe I'll pay closer attention, but I don't think I hear anything anymore. I'll report back tomorrow after my drive to work.

 

[dmac1274]

I have about 5500 miles on it. It has made the noise since new.

It is deffinately not some rattle in the dash or a loose part. This is coming from the engine and sounds exactly like a lifter tick (impossible, I know, on this engine but that's what it sounds like.)

As soon as you are off idle the noise goes away. Going to see if I can get a good recording of it this weekend. Only one Chevy Dealer in town so will need to plan on seeing one in KC or Topeka.

I love this car. The suprising power from this itty-bitty engine and the 36-38 MPG average I am getting are just awesome.

 

[SooperSonic]

Correction to my previous post. My car does make a noise while at idle revs. I suppose I didn't pay close enough attention to it or it wasn't so loud for me to notice it.

I do believe its the timing chain instead of a timing belt which accounts for the idle rattling as SSpeckerwood has pointed out.

 

[dmac1274]

Correction to my previous post. My car does make a noise while at idle revs. I suppose I didn't pay close enough attention to it or it wasn't so loud for me to notice it.

I do believe its the timing chain instead of a timing belt which accounts for the idle rattling as SSpeckerwood has pointed out.

I had someone here at work say it might also be the injectors cycling... thoughts?

 

[RichieRocket]

My engine does the same thing at 10K miles. It sounds like lifter tick as dmac1274 said. But it does not happen every time it idles?

It has a "Variable-flow oil pump", so maybe at idle, when the engine doesn't need much flow (& pressure), the oil pump pumps less pressure and the hydraulic lifters sometimes don't get pumped up all the way?

 

[SooperSonic]

It's definitely possible that it's the injectors but I'm unsure. This is the first GM car I've owned and still learning the ins and outs of it.

 

[Gimpster]

I'm also thinking you guys are hearing the fuel injectors open/close. Its very pronounced on my car as well.

 

[domduduman]

Dealer Update

So I've taken my Sonic to two dealers. The first said there's nothing wrong with it. It's just the fuel injectors making that noise. However, the second dealer is currently working on my car. They said that rattling/ticking noise was due to an issue with one of the bolts in the flywheel. I have no idea what that means, but they are waiting on a part and will replace it. If that fixes the problem, I'll let you guys know.

 

[SooperSonic]

I certainly hope there's no problems with the flywheel. Time will tell I suppose.

 

[law242]

mine makes noise when going into boost, sounds fine at idle, i took it to the dealer and they gave me the excuse it was the 87 octane pinging, they told me i could use 87 though... next tank ill put 91 just to see

 

[Gimpster]

Obviously I don't know what yours sounded like, but I have heard audible knock on my car before for sure.

mine makes noise when going into boost, sounds fine at idle, i took it to the dealer and they gave me the excuse it was the 87 octane pinging, they told me i could use 87 though... next tank ill put 91 just to see

 

[AxelRipper]

mine makes noise when going into boost, sounds fine at idle, i took it to the dealer and they gave me the excuse it was the 87 octane pinging, they told me i could use 87 though... next tank ill put 91 just to see

Yeah, I ran a Data acquisition display on mine once, an it is pretty much knocking all the time under load. On 93.

Don't worry though, knock isn't all bad, and these engines are designed to run like that. Switching to 91/93 won't bring the knock down that much but it will help and make a bit more power (it lets the ECM add more spark advance).

 

[law242]

knock does not sound good to me at all. not at all happy about that. cant hear it with the windows up but with them down you sure can hear it