: Heater Question

12-31-05, 09:12 AM
Good morning everyone and happy New Year...well i have searched the forum and i haven't found an answer to my heat problem. I have a 97 Catera and when you turn the heater on it blows hot air for a few seconds and after those few seconds it starts shooting cold air. In order to get the hot air again, for a few seconds, i have to turn the heater off, wait about 15 seconds and turn it on again. I have to repeat this cycle while drive in order to keep the cabin warm. The other odd thing is when i am on the expressway, on my way to work fo example, you can feel the warm air coming out of the vents with the heater off. But once you turn the fan on you only have it for those few seconds.

I've taken it to my two shop mechanics that know my cars inside out and they don't know what it is. Any ideas before i take it to the dealer?:hmm:

12-31-05, 11:03 AM
Have you tried resetting the thing by holding on/off and auto buttons together for about five seconds.

01-04-06, 06:32 AM
Good morning...i tried to reset it but i can't tell if it did anything. How do i know it reset? Does it do something special?

01-04-06, 06:33 AM
Has any work been done to the car recently?
How about the coolant level? Is it full?

01-04-06, 07:50 PM
Nope...no work has been done recently. As for coolant levels everything is good. This just happened out of the blue...i was hoping someone had some ideas:confused:

01-05-06, 01:54 AM
Could it be a vacuum leak? Or a bad aux water pump?

01-05-06, 07:09 AM
There is a coolant bypass valve under there somewhere, maybe it's not working right.
How about something like a thermostat sticking open? Does the coolant temperature appear to be normal or is the engine running cold?

Also how's the coolant look? You could have some gunk and buildup in there that could be causing a problem in the heater core.
I just did a heater core in one of those for a leak not long ago. It wasn't much fun.

01-05-06, 09:25 PM
can you touch the heater core to see if its hot if so i think your actuators are stripped or going bad

01-07-06, 06:23 PM
Can someone tell me where the core is? I have a feelings not some where easy, but i'll try.

01-08-06, 04:26 PM
It's not even close to easy to replace.
It's under the center of the HVAC case right in the middle.
You have to remove all kinds of stuff to get to it, it actually slides in the side of the case on the passenger's side behind the glove box. You have to take all the stuff off to get room to slide the core out.

01-08-06, 07:15 PM
Well...looks like i'll have to bow down and go visit the dealer. I can only do s much. I really was hoping this was something dunb that needed to be changed.

01-08-06, 07:54 PM
Technically it's only removing parts, but then again so is any other job.
It's going to require a few tools that you might be hard pressed to find in your home tool kit (depending on what you do of course) and knowing which parts to take off is the real trick.
It's not something you want to learn on... if that is indeed your problem.
I know you have to remove the glove box, the blower and the blower housing, lots of dash trim (to get the glove box out) and you have to drain the cooling system and disconnect and reposition the feed pipes inside to get the heater core cover off and slide the core out.

Either way you do it I hope it all works out for you.

01-08-06, 09:34 PM
If you have to remove the blower and the blower box, then it's not a job for the impatient. I had to make some work on my A/C's blower once and i'm telling you it's not easy.