Hi I own a 2001 chevy blazer zr2 and yea I'm a female that can't work on her truck. My father lives elsewhere and I kind of diagnose a problem and take it to my mechanics to save on high expenses. I've done good thus far.

My truck has a k&n air filter system. I've cleaned the filter and the Mass airflor sensor. I thought what I was having go on was fixed with the sensor being cleaned but I was wrong. I've searched high and low and I'm hoping someone in here has a solution. I tried to record the sound with my phone today while driving but it stopped and it doesn't always do it.

It kind of sounds like it's my air filter, it gets real loud and sounds like a blow dryer with a bunch of air being sucked through but it's not quite being sucked through? It takes me to push on the gas pedal a bit harder to get the horse power required to get moving.. but only during this sound. It drives fine otherwise.
I had the upper intake manifold gaskets replaced ( I hope I said that right ) - would that have anything to do with this?

I don't know what else to say but annnnnnny feedback is greatly appreciated. (My mechanics whom I trust do not have much experience around this type or air filtration system - he told me to replace the filter but then I go to checkr o-reilly auto parts to special order my filter and he says it's likely not the filter as they last for many years. I bought my truck - currently paying on it from a car lot with this air intake system already on it so I'm uncertain how old the filter is but it's been cleaned properly twice)
Thanks in advance.

 

Does it happen in the morning and/or when your truck gets hot?
I believe that's the engine fan. When it kicks on, it does tend to put a good bit of drag on the motor lol.

But yeah it's pretty common on these trucks, and not really something to worry about.
If you want to get rid of the noise and drag it puts on the motor, an electric fan would help, but like I said, I wouldn't worry about it.

 

At what speed and temp, both engine and outside temp, does this happen?

If at low speed and both the outside temp and engine temp are up there, it sounds like your clutch fan is doing its job by locking up. Once the clutch is fully locked you will hear a big "whoosh" and the engine power seems to be lacking. Once you get up to speed (about 35-40 mph), things quiet down a bit and power comes back.

 

It generally happens after I leave from work, drive to my daughters daycare which is about a 15 min drive.. but not until I shut off and restart the truck.

It happens anywhere from zero to 40, anything beyond it stops. The truck isn't over the middle mark on the temp guage. and I live in arizona - it's over 100.

You sound exactly like what it is. Is there something wrong with it? It's a real loud WHOOSH, makes me think the engine is gonna blow.

 

I think it probably is your radiator fan. I have an old mini-van where the fan has failed in 'lock' mode. It sounds like a jet when I accelerate.
Another similar sound is how a school bus or box truck sounds accelerating

 

Could possibly be the AIR pump (air injection reaction) which is located under the radiator mounted to the inside of the passenger frame rail. It will come on at odd times. The rubber line & 'T' that run to the check valves could be burnt out, causing it to sound louder than it should. If the 'T' is burnt out, then one or more of your check valves has failed and is allowing hot exhaust gasses into the cold side of the system.

 

it doesn't do it all the time though