[iggy]

I've been driving a 2012 Cruze LTZ for at least three years now, and only recently after having Valve/Cam cover replaced along with intake manifold replacement , along with emissions recall work... I hear a very faint hissing... or whooshing sound that can only be heard from roughly 2200 to 3300 RPM while just lightly pushing on the throttle. If the road noise is at all loud I can't hear it, if I step on the gas hard enough to actually make the engine accelerate quickly the engine noise drowns it out...

I am assuming this has to do with the turbo, but what's really odd is I've NEVER noticed this noise prior to the recent work done on this car. The sound goes away within a fraction of a second after letting up on the throttle, it seems to take a full second or so before it initially starts ( after pushing on the throttle )... once it's started, if I let off the gas then back on the gas quickly, there's very little lag between my foot movement and the sound coming or going .

If it's normal, then I guess I just haven't been driving on enough smooth roads to hear it ( I live in Michigan, and we have lots of crap roads ).

Maybe I'm only hearing it now, because the intake check valve is working as it should ????


I don't know if it is normal though, or if there's a leak in some part of the system. I guess I should take the thing back to the dealer, but it's so faint I just don't even know if it had always been like that and I just didn't notice, or what...

Can anyone tell me if their car makes a really slight wooooshing noise while under very light acceleration between 2200 and 3300 RPM?

 

[iggy]

So, I've been really paying more attention to this sound. Originally, I thought it sounded like light spray off my wheels on a wet road surface, the first time I heard it the road was wet. Later when I heard it on a dry road, I knew it wasn't spray off the wheels, but that's sort of what it sounds like.

Meanwhile , the sound seems to vary depending on if the steering wheel is turned... It basically goes away when your in a constant turn. The easiest , most repeatable way to hear this sound , is on a very smooth , flat, asphalt road surface going straight, 55MPH or so, (2000 RPM), press the accelerator lightly and gradually accelerate to 60 or just above 60MPH. I hear a sound that seems to correspond with changes in vacuum/boost. ( I have Torque app and see vac/boost that way ). The sound starts even before going into boost, it continues up into max boost. If I turn the steering wheel a little while this sound is occurring , the tone of the sound changes, or even goes away completely when cornering.

So, now it seems this is somehow linked to the steering system... maybe part of variable power steering? It's my understanding that the power steering is driven by a electric pump, so I don't think it's the steering pump, since the sound seems also highly coupled to the vacuum/boost.

Has anyone got a clue as to what could cause a 'shhhhhhh' type of sound that is linked to vacuum/boost and steering? Maybe also linked slightly to speed of the car?

 

[obermd]

I'd guess the new cam cover isn't seated and/or secured properly.

 

[Robby]

I can't think of anything to offer on this one.

Rob

 

[lakemg]

Sounds like you're hearing the turbo. Mine makes a similar sound. As soon as I ease off the throttle, the sound goes away. It's very faint, but more prominent when I'm accelerating up hill. See if you notice it more going up a steep incline. I bet you just never noticed the sound and it's been there all along. Took me a while to notice it too.

 

[iggy]

Sorry I haven't been around to respond to this, I'll give the full update now...

So, I took it back to the dealer, talked with the mechanic who did the work. He went for a ride with me, he heard the sound in question, but did not think it was related to work he did, wasn't exactly sure what the sound was from either. He looked under the hood , listening for any signs of vacuum leaks and such, didn't find anything abnormal . He told me that if it got any worse come back and they'd take another look. I agreed that would be the right thing to do.

Well time went on, the noise persisted but did not go away. I figured it must have been there before and I didn't hear it until after the repair.

The funny thing is... Spring time rolled around, took my Blizzak tires off for the summer, the noise suddenly went away. It apparently was the tires.

So, you may think... duh, you didn't say you had snow tires on the car. Well, my wife's car has the exact same snow tire, I mean the same size , same model tire... only difference in her tires and mine, are that mine have one winter more on them then the ones on my wife's car. The cruze I drive is 2012, the one she drives is 2013. The noise was not present on her car... so I had no reason to believe it was the tires. But... well it was the tires.

I told my mechanic friend about the tires, he just kinda nodded. He's told me about cars where he's changed out transmissions before trying to resolve noise problems for customers before, only later to find out by replacing all the tires , that it was the tires. Now, the fact that he admitted such a thing to me , makes me trust him even more... but then, maybe a dealer should have a spare set of tires laying around to put on customer cars to rule out such things. ( probably only happens that it's tires , once in a blue moon I guess ).

So anyway... moral of the story is... funny noises that persist ... have you check to see if it might be the tires?