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Discussion Starter · #1 ·
Hello

So a while back I did some work on a fuel pump and needed to reset the codes. By accident (not knowing) I reset the codes while the car was on or had was in the ignition position. Afterwards I read I shouldn't have done that. Immediately after I noticed a whirring noise from the fan like it was a mack truck. I drove it around for a while and the noise went away a little bit. I've included a video for ref. (not mine but similar noise)https://www.youtube.com/watch?v=SMZyJWUsSSs

Since the fuel pump, I've replaced the fan clutch and the power steering pump. (not related)

6 months later the noise is still very noticeable, sometimes it's quiet and you can't hear it. Other times it's very annoying.

I've read its the aux. fan but I'm not sure if something happened with the computer as the noise started when I cleared codes.

ANY HELP IS APPRECIATED.
 

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Behr fan clutch is all I use on these cars.
 

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Discussion Starter · #5 ·
Check that the fan blade on either fan is not brushing anything, viscous clutch fan is primary suspect - then read this itf you recently changed the clutch fan

http://forum.e46fanatics.com/showpost.php?p=17138890&postcount=6
Not sure the brand. But I will look into the water pump.

Update* I've noticed that the wooshing noise on acceleration only occurs after the engine has warmed up. The first 15 min of driving on a cold start there is no fan noise. This makes me think it's the aux fan and not the fan on the fan clutch. But I'm wondering if it's electrical or dme related as it only started when I incorrectly ran codes.
 

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Your fan clutch may be working properly. Based on the video the problem is NOT the Aux electric fan. If you want to rule the Aux electric fan out, just unplug it.

You went from a worn out, non functional fan clutch to a replacement that may be working properly.

You claim the fan is quiet for the first 15 minutes on cold start. It may be that the local temps are very high compared to a few weeks ago and you may also be running the AC.

Could even be the Aux electric fan is not working properly so the mechanical fan thermostat is closing and making the mechanical fan work harder.

You need to monitor the engine temperature and make sure the Aux electric fan is working which can be hard to make sure it is working 100%.

You may also have debris built up between the AC condenser and the radiator and/or damaged or missing air ducting as well.

Use the Weather Underground to track historical temperatures for your location and see what happens at night with the fan with it is cooler outside.

You need to learn how to use the Hidden OBC Menu to monitor the engine temperature as well.
 

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Not sure how much OP has driven on the new fan clutch but before I did the electric swap, I replaced my fan clutch with a Behr one. It took a little bit of time to break in I guess because it made the semi truck noise right after it was installed but eventually went away
 

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Many cheap aftermarket fan clutches are engaged too much and cause excessive fan noise

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

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And you have to be CAREFUL if the fan clutch does not slip at higher RPM's, the trash truck noise means the fan is SPINNING FAST.

Fast spinning fan = shrapnel aka, new fan, shroud, hood, radiator, radiator hose, MAF and other wiring on the front of the engine.
 

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Discussion Starter · #10 ·
Many cheap aftermarket fan clutches are engaged too much and cause excessive fan noise

Sent from my SAMSUNG-SM-G870A using Tapatalk
So this noise was happening BEFORE i installed the new fan clutch. I installed the new fan clutch because the old one had some play in it and was causing a rattle. You're saying its possible the noise continues because its a cheap replacement? Hoping you can explain why the noise was there before I replaced it.

If i loosen the bolt will that help? I did tighten it pretty tight.

Seems like things to try are

1. Unplug the aux fan and see if the noise is still there while monitoring the car temp (the car usually doesn't over heat according to the temp guage)
2. Replace the clutch fan with Behr
3. Change the water pump

any other suggestions I'm missing? Including loosening the clutch fan bolt, although this doesnt seem like a good idea.
 

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Do not loosen the fan clutch, bad idea.

Time to get a professional that understands what is going on to look at this car.
 

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It is normal for a new fan clutch to be engaged initially after installing. The fluid inside needs to move to the correct areas to allow the fan to freewheel. After replacing a fan clutching I run the engine at 2000-2500 rpm until the fan disengages, this should be less than a minute. As jfoj said use behr fan clutch (oem) and that should take care of the problem.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

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Discussion Starter · #13 · (Edited)
Do not loosen the fan clutch, bad idea.

Time to get a professional that understands what is going on to look at this car.
Noise isn't my main concern. I plan on chaining out the suspension as I noticed play in the steering and vibrations.

The vibrations seem like it might be the water pump in addition to the control arms as it's not just the steering column.
 

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Not sure why it hasn't been mentioned yet - why didn't you simply do the electric fan conversion?
I assume your car is automatic, hence why it came with both electric & mechanical fans.

Get rid of that mechanical one - it causes nothing but problems and it isn't necessary.
Electric conversion is plug and play. My Behr fan was around $160 and has been working flawlessly.
 
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