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Loud blowing noise

3K views 27 replies 7 participants last post by  Droidster 
#1 ·
When accelerating I hear a very loud sucking (or blowing) noise from the engine. It sounds like a vacuum with the hose covered. Is this normal or is something bad or blocked?
 
#7 ·
Have you noticed a change in engine temp? I know your car runs cooler than mine.

Although I haven't tried it, I have read about using a loosely rolled up newspaper to check the clutch fan. When the engine's cold, it's easy to stop the blades from spinning. When it's operating temp or higher, the blades should cut the paper.

Perhaps some members here can verify if this test works.
 
#9 ·
LOL. I think the test can also be done effectively by testing the cold car before starting it, and a warm car immediately after shutting it off.

I also don't like putting things in the path of fast moving parts. You never know if it's going to rip that newspaper out of your hands, get jammed in the belts and cause some unsuspected damage. When the test can be done with the car not running, I just don't see the need for it.




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#10 ·
Oh. I recall that an Infiniti I had owned had a seized fan clutch. The sound of the car was indisputably described as "sounds like a truck at higher RPM". The viscous fan clutch should have a max speed even at higher temps I believe, never totally locking up.




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#12 ·
"Oh. I recall that an Infiniti I had owned had a seized fan clutch. The sound of the car was indisputably described as "sounds like a truck at higher RPM". The viscous fan clutch should have a max speed even at higher temps I believe, never totally locking up."

Yup that is what it sounds like.
 
#20 ·
The thermal fan clutch is a little more sophisticated and operates, as the name implies, in response to underhood temperatures. When the engine is cold, the fan is disconnected; when too much heat is generated, the fan is allowed to cool the engine. A bi-metal thermostatic coil mounted at the front of the clutch senses the underhood temperature and operates the clutch accordingly.


SO....cold it should spin fairly easy.
 
#23 ·
Really....we are just giving you ideas of what to look for.


Your problem APPEARS to be FROM WHAT YOU HAVE SAID....the fan clutch. It is between the fan blades and the water pump.

Looks like this:
 

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#24 ·
Basically....your fan blades are there to cool a hot engine at low speeds or idle. At higher speeds, the air moving through the engine compartment from the vehicle moving forward is enough to do the job.

So...when cold the clutch fan should not be fully engaged. And at higher speeds....it should not be engaged.

It should only be engaged when the engine is at operating temps at idle or low speeds.....at which point you won't hear it.

IF... during acceleration and at higher speeds....you hear the roar of the fan....it is probably not disengaging....therefore a new fan clutch might be in order.


Will it hurt your engine?.....No. It will rob you of some horsepower and your mpg might drop a bit. And it will slow the warm up period of the engine.


Have you checked your air filter (clean?) and the air filter housing to make sure everything is secure?
 
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