Why does the needle stay on hot after putting new thermostat in a 96 cavalier

In the book a 96 model only fits 96-98 cars.
But the actual pump may be the same. You get an assembly including float and lines when you buy a new part.
You may be able to look at a new assembly for each year and tell if the actual pumps are the same style.

The most common cause is that you were given the wrong thermostat when you purchased it. The second most common problem is that the thermostat was installed upside down.

Two ideas.

1. Try a new radiator reservoir cap (trust me, it is very important in holding pressure which keeps the coolant from boiling out).

2. This one you will need an entire weekend to spend on this. You need to remove the thermostat and replace the thermostat housing. pull one of the radiator hoses and attach a garden hose with good pressure. It needs to flush for at least 20 minutes. Then switch directions and flush water where was coming out. Then put it back together and drive until it gets hot. Allow it to cool for 45mins (to prevent engine from cracking due to rapid cooling) and repeat until no crud comes out when flushing.

Sounds like your thermostat is bad or at least sticking. Replacing it is faily simple and even the good ones are less than 20 bucks. Hope this helps! (rate if useful)

when you start the car and let it warm up, does it reach normal operating temp.? Does the needle stay in the middle? If not, it's time to replace the thermostat. If it's ok, then your blend door is stuck or broken and may need replacement or repair. when you move the control to hot or cold, the blend door opens accordingly allowing cold hor hot air in.

you might have to put in a lower temp.thermastat so like if it has a 195 put in like 180 or whatever you can get that is cooler than whats in it and it should say the temp.right on the old thermastat.Call a parts house and ask them what temp ranges of thermastats they have for your year make and model of car.

you can use 10w 30.if you live in a warm or hot climate.if you live in a colder climate.you use 5w -30 oil.

Check the catalitic converter for being plugged up.

i just had this fixed on my cavalier.i put a new ground wire on my car and a new cluster and now everything is fine.

I have a 96 cavalier and if i forget to turn the gas cap until it clicks air gets in the tank and the ck. engine light comes on. So, don't forget that could be part of the problem