95 grand am engine overheating

[drisghanis]

well, got me a overheating problem on what is now the third engine in my car. it is fine when i'm driving but if i am sitting at a light it starts to overheat. also while driving on the highway there is a whining sounds just wondering if it is my rad fan.... since i have a brand new thermostat and all new sensors and relays...

any help would be appreciated thanks.

[xeroinfinity]

Welcome to AF.

It would help to know what engine .....

You said all the sesnors were replaced,
how about the temp sending unit?

If thats faulty the fans may not run.

Though Is it realy overheating or just running hot?
On the over heating, I mean into the red on the temp gauge . And or getting so hot the engine shuts down.

Running hot at stops can be normal if the cooling system isnt working properly, dirty radiator, mass build up in the cooling system.

Have you flushed the cooling system anytime recently?

On the whining noise I dont think the fan would make such a noise unless it was damaged. Could be a water pump, a wheel bearing

You'll probly have to isolate the noise a little better.

[drisghanis]

its a 3100 v6.

a friend told me that the barings in the fan where shot if you give it a spin by hand it makes a slight whine. so i thought it was that. but what kinda erks me is that the whine only happens when i'm out on the highway doing about 80 and i press the gas. if i am just coasting without pressing the pedal it doesn't make the noise at all....

yeah i put a new engine in it so all new sensors, filters and coolant. waterpump is used but in good condition.

[xeroinfinity]

Ok on the overheating,
I know you said you replaced things but have you used any engine coolant flush ?

If the resevoir is nasty and looks like rusty crud and your radiator looks the same then I would run some sort of chemical treatment(like prestone) to clean the cooling system.

This might help, though you could have a bad LIM gasket.

The fan could make the noise...
If you get some wire and hook the fan directly to the battery and see if it whines. Hopefull thats it.

Let me know what you find out.

[lebky]

Hmm I think at 80 mph your car has adequate cooling from the wind resistance I do not see the reason for fan to be on at that speed, unless you have AC on. As XI said make sure it is the fan by using jumper wires. But I just wanted to add something - be careful with noises they can transfer thier frequencies and you can think something under your hood is whining but later you find out that it was your fuel pump. Fuel pumps are famous for their wining sound when they are about die. I am not telling you that it is your fuel pump it is just an example. Good luck.
Since summer is comming soon, I was thinking to connect my cooling fan with the brake switch so any time I press the brake pedall the fan will be on. It is good for city traffic. I think it is possible to do someting like that without interfering with pcm comanding the same fan on. What you guys think?