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97 transam ws6 vaccum noise fan when turning key off normal?

1K views 7 replies 3 participants last post by  GaryDoug 
#1 ·
So I purchased a 97 transam ws6 and when you turn the key to run position or turn over the engine and then turn the key back shutting engine off or even if you just turn it to run position and then back to off the engine makes a weird noise that sounds exactly like a vaccum cleaner. We looked it over and figured out on the dual radiator fans it's the left radiator fan making this really weird noise when turning the key off. Is this normal? If not what would this mean? Need to be replaced bad fans? They work normal besides this. U have a 93 formula and it doesent do that. Thanks
 
#2 · (Edited)
This is not normal behavior. The fan should not have power going to it when you turn key off on a 93. Might want to download the 93 service manual in the sticky threads of 4th gen section.

Then go to electrical section and look at the fan troubleshooting chart. Since the fan relay points are fed hot from a fuseable link, the relay coil is where you should be looking for trouble.

It is fed hot only when ignition switch is on. So maybe someone has monkeyed with the wiring, or something is causing relay coil to have power with key off.

BUT, even with power on the relay coil, all the time, fans won't run unless the relay coil ground is supplied. From factory this is supplied by ecm. So you might have a intermittently shorted ground wire.

These are guesses based on fan wiring. You will have to troubleshoot the problem. It could be the electrical part of ignition switch causing trouble also. Or an ecm gone crazy.
 
#3 ·
Are you saying the fan runs a lot after turning off the ignition or that it runs a short time but makes a lot of noise?
It could be that the relay is sticking on. Or if it just makes noise, could be bad fan bearings.
 
#4 ·
1993 doesent make any noise in the fan 1997 does. When you turn the ignition off on 97 the left side fan makes a vaccum cleaner noise for about 3 seconds and then goes silent basically you turn the key off (back) and it sounds like someone turned on a vaccum cleaner and turned it off very short but weird. It was hard to see but it was coming from driver side and freond looking under hood said when it made that noise he could see the left fan spin for a second when it made that noise.
 
#7 ·
vaccum noise video

Ok so I haven't had a chance to get to car in storage to film video of noise but when looking at videos on YouTube of lt1 trans ams this video actually has the same exact noise in it. Right in the begining of the video when the kid starts the car you hear the vaccum type noise loud and clear. It's the same noise I'm talking about. So please look and let me know what you think it is or if your opinions are still the same. Here's the link to the video. https://youtu.be/Jexqe3-HqIM
 
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