Strange noise in 1.6 16v Ecotec Sonic

[ramiro77]

Hi guys.
I have a Sonic with 1.6 16v Ecotec engine.
ALL of this engines makes a strange noise in accelerating or making force. It´s sounds like something knocking.
The Cruze makes the same noise but with a different engine (1.8 16v), so I´m wondering what is that noise.
Nobody seems to found a fix for this. Every dealer said that this is a "caracteristic sound" of the car. But I don´t know how this can be normal...

This is the sound in a 1.2 Sonic when it starts. Something like a fast knocking sound:

Chevrolet Aveo 1.2 16V 86ch LT - YouTube

Any of you had the same trouble? It´s not the sway bars links. I know that issue and which sound it makes.

 

[Maddmatts]

If it's just happening while accelerating/braking then it might be loose engine mounts. And it's wouldn't be the first time that's happened here.

 

[ramiro77]

Thanks for reply Maddmats!
But no, it happens while acelerating in neutral shift too. And never while breaking.
All Sonics in my country does this knock sound. But no dealer found any fix for this. They only said that this is a "caracteristic sound of Sonic and Cruze". Of course I don´t belive any of this, and that´s why I came here.

 

[qwed94]

Well you may have came to the wrong place actually because here in the USA --- Sonics and Cruze do not have that particular powertrain. It might be characteristic.
You might try sitting still, hitting gas pedal (not to the floor, but accelerate somewhat) if you dont get this noise at all, then you know it might be something in the suspension. If you still get the sound, it is likely something in the valvetrain area.

 

[ramiro77]

I know that. But the Cruze comes here with your 1.8 16v engine. And it does the same annoying noise!
I get the noise hitting the gas pedal too, but a little less louder. So its not a suspension issue. And I forgot to tell you something: that sound makes the car vibrate. I can feel a lot of vibration in my feet.
The Sonic from the video I quoted here has 1.2 16v engine, and it does the same noise. Another engine, another country, but the same issue. Sadly, Im running out of ideas...

 

[qwed94]

Well I simply overlooked that in the original post. I have a 1.8 in mine. Makes no knocking noise at all. I have heard of motor mounts coming loose and even breaking. That is likely what is wrong with yours. (I do understand your being upset, I would be too). I also know that there is absolutely no way under the sun that you have personally heard "every single Sonic & Cruze in your country". That is exactly what makes this hard to analyze though. Is it really that a lot of them really do knock !! Or basically just yours and your dealer hasnt fixed it? (Therefore causing horrific anger in you). Your car should have 100k mile warranty and the dealer might be holding off till it blows up. A new engine replacement is easier/cheaper than a overhaul of yours.

What I mean is, a knocking noise during acceleration, and quiets down immediately when foot is removed from the loud pedal can easily be a rod going out. Could be a loose motormount. Either one could have been an honost "BOO-BOO" at the factory. If it makes noise at startup then quiets when engine gets warm, could be a bad wrist pin. (That will never cause a problem in itself. 200k miles later it will still run, with that hammering sound). If it is a ticking sound at startup then goes away. It is likely a bad lifter, or a unproperly adjusted valve. Will never cause problem either.

This is why it is important to be kind of honost with the number of cars that you have heard do this. If most of them really do. Then you are not the only complaint, and Chevy will eventually call for a recall (likely). If yours is the only car that knocks, then take it to another dealer with your complaints. They will either fix it now, or wait till it goes boom-boom.

 

[qwed94]

I guess I should have watched the video first. I still did not hear a single knocking. All I heard was the same louder exhaust noise that I hear most of them make. The exhaust they use on the Sonics is fairly free flowing. I heard the vroom, but definitely no knocking/ticking/clanging/or clunking.

 

[ramiro77]

Thanks for reply qwed94!
When I said "every sonic in my country does this" is because we have a regional forum for Argentina. And EVERY single person in that forum has the same strange noise. Happens with the Cruze too.
Dealers knows that there is a strange noise coming from the engine. But they all keep repeating that this is normal and a "caracteristic sound" from this cars. We don´t belive any of this because we are used to lies and corruption when it comes to money.

Do you really didn't hear that noise from the video? It´s something like a "clocloclocloc" when he puts first gear and he starts moving turning LEFT the wheels.

 

[sx sonic]

At what time in the video does it make this noise (for example 1minute 34 seconds).

I did not hear anything out of the ordinary.

Have you heard this noise on any other cars? Like a ford, mercedes, etc?
If you say almost everyone in your forum has this noise and across different engine platforms then it is logically normal. That or they made more defective cars than good ones.........

 

[ChrisJ]

I didn't watch the video but I'm going to assume hes concerned about either valvatrain or injector noise both of which I think are audible on the 1.4 and 1.8. I know the injectors are VERY noticeable.

 

[ramiro77]

sx sonic:

It does the noise at exactly 0:22. Something like a fast and loud "knock knock knock". My feet vibrates with that noise too. And yes, that noise is in all Sonics and Cruzes around here (Cruzes with 1.8 16v engine). I´ve NEVER seen this issue in other car.

ChrisJ:

The valvetrain noise is more like a loud sewer machine. I´m familiar with that sound in other cars but this noise is not even close to this. And injector noise is more like a "tic tic tic". Besides I don´t think valvetrain or injector noise can make my feet vibrate like something hitting the floor of the car.

I went to my mechanic guy and we took a look to the engine. We both agreed that the sound comes from the intake manifold. And if we touch the intake manifold, we can feel the noise vibration if somebody else is acelerating the car in 1st gear or reverse. But everything looks fine, including engine mounts and front wheel train. There is nothing loose...