2000 Oldsmobile Silhouette Whining noise and AC problem

Tiny
BECKYP
  • MEMBER
  • 2000 OLDSMOBILE SILHOUETTE
  • 160,000 MILES
Ac seems to be freezing up sometimes. When on 5 it will work for a bit then just shut off. Turn it down to 4 and it comes back on. Rear ac does not work most of them time but will come on once in awhile. Have replaced filter inside van. Whining noise starts at crank up and gets louder with acceleration.
Friday, September 20th, 2013 AT 8:39 AM

10 Replies

Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Just a thought, if 1--2--3--4--5 is the blower motor speed, That is the circuit I'd check out. If you think the refrigerant is low, have a shop check it out.

Any hvac trouble codes? Some of the national brand autostores will check codes for free.
Was this
answer
helpful?
Yes
No
Friday, September 20th, 2013 AT 10:02 AM
Tiny
BECKYP
  • MEMBER
  • 5 POSTS
Yes the blower motor speed is correct. Refrigerant is full. Checked codes at local store and nothing is showing but still no air blowing in rear vents and still freezing up during hot part of day. Whining noise starts at crank up and gets louder with acceleration and also increases in sound when AC is turned on.
Was this
answer
helpful?
Yes
No
Friday, September 20th, 2013 AT 5:08 PM
Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
That #5 in your first post, is that the front blower speed? If the blower motor isn't working, I'd have to check the blower motor and wiring circuit.

If the blower motor is running but no air coming out, I'd have to check the hvac actuators. If you think the evaporator is freezing up, I'd have to visually check and see.

The whining noise could possibly be the belt, maybe the compressor.
Was this
answer
helpful?
Yes
No
Saturday, September 21st, 2013 AT 7:51 AM
Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Just to add, I'd have to check voltage and ground to the rear blower motor. When you talk about froze-up, are you talking about blower motor being froze-up or the evaporator/whatever freezing up from moisture?

I apologize if I misunderstood your post.

Click on the wiring diagram for rear blower motor. The brown wire is voltage, the orange wire is ground. Check them both. If good voltage and ground with no blower action, suspect the blower motor.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
Saturday, September 21st, 2013 AT 8:32 AM
Tiny
BECKYP
  • MEMBER
  • 5 POSTS
The #5 is the front speed. It will blow air out of vents but then all of a sudden it just stops completely but if I turn it back down to 4, 3, 2, 1 it comes back on and air blows out normally. All in front section of van. When I say freezing up I mean the hair will be blowing fine on speed 4 or lower and then all of a sudden the air does not seem to be blowing as cool and I can see white air coming out of the vents. Again all in front section of van. The rear air does not come on at all most of the time but occasionally it will come on for a few minutes and then shut back off.

I have checked belts and can not find anything wrong with them but then again I may be wrong not sure. The whining occurs while ac is off and while ac is on just increases in sound with ac on. And whining increases in sound with acceleration of mph

I will try above suggestions and see what happens.

Thanks
Was this
answer
helpful?
Yes
No
Saturday, September 21st, 2013 AT 10:33 AM
Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Has the belt ever been changed? Also, check the tension on the belt. If the evaporator is freezing up, after you turn off the vehicle and it sits for a while, it thaws out, then the ac works normally again, for a while. Is that what happens?

You need somebody to put a set of manifold gages on the ac system, to see the pressures.
Was this
answer
helpful?
Yes
No
Sunday, September 22nd, 2013 AT 12:01 PM
Tiny
BECKYP
  • MEMBER
  • 5 POSTS
I am unsure if the belt has ever been changed. I purchased the van used last year. Yes that is what happens to the ac. Exactly how it happens.

I will have someone check the tension on the belt tomorrow.

Thanks
Was this
answer
helpful?
Yes
No
Sunday, September 22nd, 2013 AT 1:49 PM
Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
No problem, have a good day.
Was this
answer
helpful?
Yes
No
Monday, September 23rd, 2013 AT 7:28 AM
Tiny
BECKYP
  • MEMBER
  • 5 POSTS
Just got back from a shop and the whining noise is the power steering pump going out. Still have to check the ac wiring.
Was this
answer
helpful?
Yes
No
Monday, September 23rd, 2013 AT 10:02 AM
Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Just for future reference, accessory noises, You can use a long metal bar, engine idling, place tip of bar to accessory housing. I place the other end of bar on that bone behind my ear, it magnifies the sounds. Check each accessory body in turn. You should be able to tell where it is the loudest. Just be careful not to get anything caught in belt or pulleys. Safety is your responsibility.

Sorry I didn't think about that earlier.
Was this
answer
helpful?
Yes
No
Monday, September 23rd, 2013 AT 11:12 AM

Please login or register to post a reply.

Related Air Conditioner Not Working Content

Fix an Air Conditioning Not Working Video
VIDEO
Fix an Air Conditioning Not Working Video
In­struc­tional re­pair video
Air Conditioner Not Working
GUIDE
Air Conditioner Not Working
Like any sub sys­tem in to­day's car a prob­lem and be mi­nor or a lit­tle more in­volved, this guide will help you find the prob­lem and per­form re­pairs. You can be the judge if...
VIEW MORE