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My car makes a swshdddd Noise when I press the gas

I have recently, and by recently like 3 days noticed my car was making this weird shhhddddshdddshhhddddd noise when I accelerate. I am not sure what it might be. My tires need changing, could that be a factor? It’s not a hissing like it’s overheating. In January I had a problem where they had to change the lower engine block because my coolant and my oils where mixing. The noise almost sounds like a fanish or beltish noise…I am a girl who doesn’t know much about cars. please help.

Without actually hearing the noise, all I can say is to have it checked asap. If the noise varies in pitch with engine speed (how fast the engine is going, not how fast the car is going), it could be a bad belt or a bad bearing in something driven by the belt. It could also be an exhaust leak.

Get it checked out before it turns into something really expensive.

Hmmmm…
Oblivion got me to thinking about a late '60s Chevy that a friend loaned me many years ago (1971) the exhaust of which made exactly that sound.

I “second” his recommendation.

Would it possibly be coolant rushing thru the heater ciore caused by low coolant?

Without hearing the sound it’s impossible to guess. Anything is possible.

No, coolant rushing through the core makes a blopblopblopsshdhshhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh noise.

The fact that this occurs only when you accelerate is concerning. If it occured all the time, or only when you were going fast say, but not accelerating, then it might be almost anything, but there’d be a good chance it could be something easily fixed and not very expensive provided you fixed it quickly. But b/c it only occurs when you accelerate, which is when the engine and all the parts that make the car go get stressed the most, I think this may prove to be expensive.

What are the possibilities? It’s possible it is the tires. It might be the motor mounts shifting, causing a clearance problem somewhere. It might be the suspension system causing the tires to rub against something. If you have CV joints, one of them might be on their last legs. It could be the internals: engine bearings/rods/transmission. Hope it is not that. Anyway, I agree w/the others it is important to get this looked at both for your safety and your wallet, and get an opinion offered by someone with expertise of your make and model asap. You are welcome to post what they tell you here again if you like.

I’d be extremely surprised if the problem turned out to be the tires. Is there any way you can describe the noise better?

The only reason I included the tires is the nature of the described noise. That kind of sort of a cross between a shudder and a hiss and a thud – shsd shsd shsd – can be a symptom of a bad tire. But that sort of noise usually occurs independent of whether you are pressing on the gas or not. If you are moving fast enough, you hear it. So you are probably correct @oblivion, but since tires are known to be an issue on the car and it’s quick and easy for a mechanic to look at the tires, tires as the cause shouldn’t be completely eliminated. I think it likely it will be the first thing the mechanic looks at.

@GeorgeSanJose I agree that all kinds of funky noises can be caused by tires. Since the OP said this was under acceleration, and apparently not continuous, I’d more suspect an exhaust leak though.

Me too. My friend’s Chevy only made the sound when I punched the accelerator pedal. Exhaust leaks tend to act that way.

I had car that would whistle a nice C# when going over forty – and not all the time but when it did, it was loud. It would drive me nuts.

The roofrack was missing a plastic plug and the wind would blow across it, making this perfect note, much like you might blow across an empty beer bottle.