[BTW_S10]

I started the truck with the AC on cold and blower motor off. When running I switched it to hot and the blower motor on 4. After that a loud squealing/ rattling noise now is present when the truck is running only. Unplugged blower motor and sound still occur. When only power on not running with blower motor on the sound isn’t presents.

 

[Rebel n Dirt]

Year, and engine would help.

 

[BTW_S10]

Year, and engine would help.

1989, 4.3 L v6.

 

[BTW_S10]

I started the truck with the AC on cold and blower motor off. When running I switched it to hot and the blower motor on 4. After that a loud squealing/ rattling noise now is present when the truck is running only. Unplugged blower motor and sound still occur. When only power on not running with blower motor on the sound isn’t presents.

I am now getting slight loss in power steering as well and when I move the wheel left or right the battery light flashes on and off as well. So I will presume it’s a power steering line, pump or rack.

 

[Rebel n Dirt]

first off you do not have a rack, it's a steering gearbox. They are a bit more durable than racks are. As for the steering going wonky, how does the fluid level look? These pumps get a bit noisy when low, and will also restrict movement when low too.

 

[BTW_S10]

first off you do not have a rack, it's a steering gearbox. They are a bit more durable than racks are. As for the steering going wonky, how does the fluid level look? These pumps get a bit noisy when low, and will also restrict movement when low too.

I’ll go ahead and check the fluid and fill it accordingly when I get off of work. I appreciate the help and was also unaware of a steering box vs rack.

 

[oldeerslayer]

Have looked watched the belt when it's running? Something else may not be turning, like the alternator or A/C compressor or an idler pulley might be shot.

 

[BTW_S10]

Have looked watched the belt when it's running? Something else may not be turning, like the alternator or A/C compressor or an idler pulley might be shot.

I do have new battery, alternator, plugs and wires in there from when I bought the truck one year ago, I put them in for my previous headlight issue. I have had a small, quiet squeak from the idler pulley but besides that the belt it all fine. I’ll have to check the A/C compressor since that has always been audible when the truck it on and running, do you know how I go about checking the compressor? I’m unaware of its location.

 

[oldeerslayer]

 

[BTW_S10]

I started the truck with the AC on cold and blower motor off. When running I switched it to hot and the blower motor on 4. After that a loud squealing/ rattling noise now is present when the truck is running only. Unplugged blower motor and sound still occur. When only power on not running with blower motor on the sound isn’t presents.

MY SOLUTION: Thank you to rebel n dirt and oldeerSlayer for the replies. Turns out my idler pulley went bad the same time I turned the AC on leading me to believe the noises were connected. However the bearing in my idler pulley seized up and chewed it to bits. Advanced auto had the part in stock and it was a 30 second fix. One 15 and a 16 to loosen the belt assy. I was also a wee bit low on Power steering fluid anyway so I filled her up.

 

[oldeerslayer]

Good job.
Glad to hear you got it fixed and what the cure was.
It always nice when a member replies with the fix rather than leaving us wondering if he ever did find the issue.

 

[Rebel n Dirt]

Glad to hear all is well and quiet in the truck now. If you ever need anything else feel free to ask, that's what we are here for.