2001 Chevy Impala... Temp guage and heat/ac problem?

Question

Every time I turn my heater on with the rear defroster at the same time, my temperature guage goes all the way down pass the cold position (It also has happened when I only use the ac or heater) and then my heater will start blowing out cooler air... and if I switch it to the ac, It stays at the same temperature.. Then once I turn the car off, the fans keep running for about 5-10 minutes and if I drive it like that for a long period of time, the check engine light comes on and the codes says that the engine is running hot... if i disconnect the positive battery for a few, everything goes back to normal including the fans and the guage until I mess with the heater and defroster. I have drove the car for over three weeks without messing with the heater or anything and nothing went wrong but yesterday I turned it on and about 10 minutes later the guage slowly went down.. I also replaced the cooling sensor a few weeks ago

Thanks... You just reminded me... The coolant light comes on now too. And it stays on no matter what

Answer 1

You did not say what code you were getting so i am gonna guess this may be your problem.

Vehicle: 2001 - 2001 Chevrolet Impala 3.4L
2000 - 2001 Chevrolet Impala 3.8L

Symptom: The check engine light comes on, trouble code P0128 is stored, the temperature gauge is inoperative and the cooling fans are running.

Codes: P0128

Problem: Faulty thermostat

Test & Fix: The default of a trouble code P0128 is to run the cooing fans and make the temperature gauge inoperative. This code indicates the engine did not warm up as fast as it should have. Check for the thermostat to be stuck open. Replace the thermostat and retest. Monitor the engine temperature. It should reach 195 degrees F within a few minutes.

Answer 2

You're low on coolant. When you turn the heater on, the coolant drops below the point of the sensor.
Or, you have a bad ground wire between the engine and the frame.

Answer 3

i own a repair shop,and it sounds like it could be really low on coolant or have a very weak water pump on it, id have it checked out,what its doing isn't normal for a car to do,one other thing that can cause this ,is a bad thermostat in it,combine that with low coolant and you,ll get what its doing now,id check all of this though,good luck with it i hope this helps.

Answer 4

a million. replace your flasher relay. this is the main probable reason to your turn sign/ disadvantages concern 2. Your cruise administration and horn no longer working are maximum probable by way of a nasty clockspring. It could get replaced for the two one to artwork