Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
HiCustomer Thank you for asking your question on Just Answer.
Do the temperature gauge move at all, after the engine has been running for about 5 minutes?
Do the engine cooling fans come on when the engine is started?
It sounds like your thermostat may be stuck open. I have the same issue with my 2001 Chevy Van, and it seems to take forever to get warm, and my heater is real slow to get going, but it does work eventually.
If I let it sit and idle for a while (like in the driveway or when sitting in a drive-through), then the gauge will go up to around 200 degrees, because no air is flowing through the radiator. Then the air temperature coming out of the heater vents gets up to about 120 degrees (I have measured it).
If you want the instructions on how to change the thermostat, please let me know. But what I would do first is check the heater hoses (going to and coming from the heater core) and make sure they are both HOT to the touch once the engine is warmed up. If both sides are not hot, you could have a flow problem through the core.
I would also make sure that the cooling system is absolutely FULL. Sometimes when it is a little low, there is limited flow of coolant through the heater core, and you will not get much (if any) heat transfer from the core. You can check the level in the radiator when the engine is cold. It should be right up to the top of the radiator neck. If not, start the engine and watch the level as the vehicle warms up. You should see it drop when the thermostat opens, or it will drop and you will see it flow if the thermostat is stuck open. Just top it up to FULL, once you see it flow, and put the cap back on. Then test the heater again, and see if it is any better.
Please let me know what you find and if you want those instructions.
Take Care, Greg A.
Hi again. Sorry about the delay - my wife was having a "computer emergency."
The heater hoses should be at the rear of the engine compartment, on the firewall.
Here is the procedure to replace them, with diagrams. This should at least let you know where they are and where they run. You do not have to replace them at this time, only if it becomes necessary.
When installing new heater inlet and outlet hoses, place the clamps on the hoses before installing the hoses to the vehicle.
Please let me know what you find.
It sounds like you have a flow problem through the heater core. I don't believe there is a control valve in the heater hoses, at least there is no mention of that in the manual. Sometimes "crud" builds up in the core or hoses and can block the flow of coolant.
What I would do is disconnect the heater hoses, as close to where they connect to the engine as possible, and flush water through the heater core in BOTH directions. You should be able to do this with a garden hose. Just make sure the engine has cooled off before disconnecting the hoses. You can also disconnect the hoses close to the core, where they pass through the firewall and flush the core from there. If there is a blockage in one of the hoses, I would just replace them (they are cheap).
I hope the core is not blocked, because they can be a real pain to change.
Did you flush both the hoses AND the core in both directions?
Are the hoses now HOT to the touch after the engine is warm? That is what will tell you if you have good flow through the core.
I have to go out for a few hours. Be back after noon (pacific time).
Excellent Work! And its nice to be warm.
Thanks for the accept & Feedback.