Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Possible coolant fan issue.

Thread Tools
 
Search this Thread
 
Old 08-30-2020, 05:31 PM
  #1  
Member

Thread Starter
 
Elthesh's Avatar
 
Join Date: May 2004
Location: Fort Lauderdale
Posts: 418
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Pontiac Trans Am
Engine: 305
Transmission: 700r4
Possible coolant fan issue.

I was driving around today and sitting in long lines at various places. The temp started climbing getting close to the red zone. I got out of the lines and drove around which got the temp back down almost immediately, within a minute or 2. I also had the AC on all this time until I got out of the lines when I turned it off, for reference. That's just the description. I assumed it was a fan issue as driving cooled it down a lot. I wasn't able to check if the fans were running before shutting the car off. I used a jumper on the aldl which caused the driver side fan to turn on at full speed, but not the passenger. I believe both are supposed to come on, correct?

Now, with the AC running, both fans should turn on, correct?
With the aldl jumpered, both fans should come on?
If at least one of the fans came on, the temp shouldn't have shot up that high seeing as driving around caused the temp to immediately go back down, right?

What would cause the following. #1, passenger fan to not turn on even when the aldl is jumpered. #2 neither fan to turn on regardless of temperature or if the AC is on, BUT would still turn on at least the driver side fan with the aldl jumpered.

I did manually spin both fans by hand and they both spun freely, and coolant levels are perfect, with no leaks.
Old 08-30-2020, 08:31 PM
  #2  
Supreme Member
iTrader: (1)
 
GeneralDisorder's Avatar
 
Join Date: Mar 2017
Location: Portland, OR
Posts: 4,255
Received 422 Likes on 323 Posts
Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Possible coolant fan issue.

The passenger fan is controlled by a thermo-switch in the cylinder head (passenger side IIRC). The ECU doesn't activate it so the ALDL can't control it.

GD
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
85Irocbuild
Cooling
35
04-25-2015 07:53 PM
RS Chris
Cooling
2
01-26-2009 11:35 PM
jbates346
Cooling
3
11-23-2008 10:07 PM
BottlesR4Babies
Cooling
8
03-06-2004 07:35 AM
sancho
Electronics
6
08-22-2002 11:47 AM



Quick Reply: Possible coolant fan issue.



All times are GMT -5. The time now is 10:02 PM.