what causes my 96 lumina to get hot while sitting still?

is your rad cap or expantion tank cap loose

no

take the belt off of the water pump and try to turn it with your hand if it is easy its bad if iit is hard it is good

im goin to do that now.

cooling fans and fan speeds are happening right? They can set codes on many years but fans can slow down due to dirt and moisture entry. I have sped them up or got them working with contact cleaner followed by wd 40. What's that noise ? whirrrr !

I expect the car to run warm when it just sits there. The radiator sits behind the open grill to let the air help cool it when the vehicle is moving. I think everyone is overthinking this a bit.

if its ok when moving circulation is ok. when stopped it's the fan that keeps it cool therefore it will be the elec fan not running. put power to the pos contact if fan works its the temp sensor switch, if it doesn't the fan is kaput

So the pump spun supper easy.. how sure r u that its bad

so this vehicle has 2 fans side by side, however I noticed only one kicking on for a very short period.

if only one is coming on you will not have enough Freon if you want to find out if you pump is bad take it of and see

A vehicles electronic cooling fan system cycles the engine cooling fan based on the cooling fan temp switch. The computer for this can increase the speed of the fan and set trouble codes. Every engine that has to sit still in traffic must run its fan every time the t-stat opens and the temp has reached op temp. The speeds increase as needs increase, additional fans are in play with A/c etc. That would mean you had one for a/c and one for engine cooling. The a/c fan has to run because hi side pressure rises immediately, and would burst without cooling fan and fail safe switches are supposed to stop compressor clutch operation. So, if you have the a/c not in a mode that uses compressor, the other fan would be expected to cycle as if the vehicle had no A/c.

If your system is filled and burped, and your cooling fan runs, but your system is going to get too hot, the fan speed control driver is designed to raise the fan speed. If your fan labors due to dirt in its electric motor, it will not raise. I would clean it, if I suspected that. Other concerns with multi speed fans can require the need of the service codes being read to continue the diagnosis. Then take the code to enginecodes.com for definitions, possible causes, etc.

it wouldn't hurt to check the relays for both cooling fans.

But is there a service code stored in the memory? and what are you checking the relays for? sure, if one was sticky, it can fail to operate to boost the speed, but these things may direct the reader to the proper pinpoint test. Guess testing a sticky one could mean you reproduce conditions and tap on it. or swap relays. or verify wires have what they are supposed to with a schematic. That's how the pinpont test is supposed to simplify not only which has what, but when and where. The test would eliminate confusion. Identifying relays is important, then like parts can be interchanged

turn on defrost position when it starts to over-heat and turn fan to low anyway to kick fan on.if it starts to stabalize then you have fan bad or relay bad or temp. control sensor bad or dirty or a short