Blower whining in the morning
#1
Seasoned Member
Thread Starter
Join Date: Dec 2011
Location: Springfield, MA
Posts: 372
Likes: 0
Received 1 Like
on
1 Post
Year: 1993
Model: Cherokee
Engine: 4.0
Blower whining in the morning
Every time i start my truck after it sits overnight (or a long period of time), the blower makes a weird whining noise that goes away after i crank the heat for a few seconds. i think it has something to do with vacuum system because i relocated my vacuum bladder and i might be missing something. I know its holding negative air because my cruise control works. When i used to disconnect the bladder, a bunch of air would get sucked in until it equalized the pressure but now that i relocated it, i dont think it's holding the pressure once the vehicle is shut down. i have the bladder mounted next the the brake master cyclinder. I ran the line directly to a plastic "T" i installed right at the intake.
#2
CF Veteran
Join Date: May 2008
Posts: 3,018
Likes: 0
Received 13 Likes
on
13 Posts
Year: 1988
Model: Cherokee
Engine: AMC242
Mechanical high-pitched sound? Kinda in between a whine and a screech?
Sounds like the bearings in the blower fan motor are going out on you. Access it (generally) on the engine side of the firewall, passenger side of the vehicle. replacing it on the XJ is easier than on most other vehicles I've had to do the job on...
Sounds like the bearings in the blower fan motor are going out on you. Access it (generally) on the engine side of the firewall, passenger side of the vehicle. replacing it on the XJ is easier than on most other vehicles I've had to do the job on...
#5
Seasoned Member
Thread Starter
Join Date: Dec 2011
Location: Springfield, MA
Posts: 372
Likes: 0
Received 1 Like
on
1 Post
Year: 1993
Model: Cherokee
Engine: 4.0
Originally Posted by Firestorm500
Disconnect heater blower motor at the firewall, or pull the fuse, let sit overnight.
If it still does it you know it's not the blower motor.
If it still does it you know it's not the blower motor.
#6
CF Veteran
Join Date: Apr 2009
Posts: 4,734
Likes: 0
Received 9 Likes
on
9 Posts
Year: 2015, 2012
Model: Grand Cherokee (WK2)
Engine: 3.6L
You said the noise happens after sitting overnight or "a long period of time". Even with the climate control lever set to "off" the motor will still run on some vehicles (for positive air flow).
You want to make sure the blower cannot run while performing this diagnostic. You can unplug it right before you start the Jeep if you think you will remember to do so.
You want to make sure the blower cannot run while performing this diagnostic. You can unplug it right before you start the Jeep if you think you will remember to do so.
#7
Seasoned Member
Thread Starter
Join Date: Dec 2011
Location: Springfield, MA
Posts: 372
Likes: 0
Received 1 Like
on
1 Post
Year: 1993
Model: Cherokee
Engine: 4.0
You said the noise happens after sitting overnight or "a long period of time". Even with the climate control lever set to "off" the motor will still run on some vehicles (for positive air flow).
You want to make sure the blower cannot run while performing this diagnostic. You can unplug it right before you start the Jeep if you think you will remember to do so.
You want to make sure the blower cannot run while performing this diagnostic. You can unplug it right before you start the Jeep if you think you will remember to do so.
Ok, didnt realize they still ran with the vehicle off. I'll give it a shot. I was playing with it this morning and i think it has something to do with the vents because the noise stops if i switch from defrost to vent or heat.
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post
pTacRP
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
14
08-01-2021 12:35 PM
kend3031
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
1
09-30-2015 08:15 AM
BluJay
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
09-26-2015 10:38 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)