I purchased my 1994 Z28 in April of this year so I haven't had to use the heater much. But since it's now Fall with Winter around the corner it would be nice to be warm in my car. Problem is that it takes FOREVER before the heater actually gets warm. I would have to have been driving it for a long time, and I watch the temp gauge go from 0 to 160, which is where it normally operates. However when I slow down taking my girls to school, soon after it raises to about 185. Even at that temp, after driving it about 5-10 minutes, the air is not warm. I drive to work, about 20 miles and still not warm. It will eventually get warm, like if I was driving around all day in the city but this is not going to work when the temp outside gets to 30 and below. I like a nice, warm, and toasty ride to work, and today when I got to work my feet were cold...

Any suggestions? We recently replaced the thermostat and one of the hoses since it had a hole, no change.

Thanks!

 

Put a higher temp thermostat in it. Like a 190 or 195. That will help alot. It'd be a good idea to start your car 10 minutes before you have to leave and just let in run outside while you're toasty inside lol. That's what I do because I have a 180degree thermostat.

 

Sure sounds like a bad thermostat. The temp rise at low speeds is a classic sign.

You should be running a 195 thermostat, but remember that no matter the thermostat rating, the engine won't warm up any faster. Any *good* thermostat stays closed until it almost reaches its rated temp.

I'd replace the thermostat again, especially if you bought a RobertShaw special at Pep Boys, Advance, or other chain. In my experience the mass market RobertShaw thermostats are junk. Buy GM from the dealer or AC Delco from RockAuto.

On the subject of thermostats, I'm about to replace the one in my 94 V6. This car is S L O W to warm up. Unreasonably slow. I own no other car that is so slow to warm up and that's saying something since some of my rides are mid-60s big block Chryslers.

 

Thanks, the thermostat was purchased from O' Reilly the 180 temp one, I imagine it's just a stock one, only cost $8. I mean literally this week it was changed because the mechanic was fixing a water hose that had broken and they were right there to fix it. Perhaps I need one from Rock Auto...sounds like a good idea...I hate taking my girls to school when it's freezing and the car is cold...

Thanks for your info, I'll give Rock Auto a look see..

 

Did the previous owner do any mods to the car? It could be that he hooked the other secondairy fan up to fun with the primary fan, that would definetly cause your problem. I have my secondary fan to come on around 180 and it keeps it from warming up quick, it doesn't heat up that slow, but then again I hardly ever use it as I'm in AZ. I would check that as see just to rule it out. Can be set up to come on early in the PCM or there is a sensor unit, or hardwired into the primary.

 

I don't think they did any mods as this car looks pretty stock to me. Funny thing though...it came from AZ....now it's in AR...a little cooler here than the nice dry air in AZ...worth looking at though. I imagine a mechanic could take a quick look and find that?? What is the PCM?? (don't laugh...I'm a newbie)

 

check to make sure the temp dial is moving the cable. if the door that lets air flow through the heater core is not working or opening part way then heat would take some time to come through. other thing is the heater core it self. have you had it flushed? it may be plugged up.

 

Craby, how are you so good?

 

Try squeeze the hot water heater line (lower line on a 95 Z28 with AC.) that go's in to the heater box, this will help remove any air out of the heater core. Just did this today on my 95 Z28 and now I have heat. The two heater lines travel below the level of the heater core and will collect an air bubble. Using the air bleeder valve didn't do the job good enough.
Having own a third gen. TA. back in Alaska, this works.
Also go to Radio Shack and buy a infrared temp. reading tool. (under 15 dollars.)

 

Valhar, I use the squeeze trick, too. Works great for vapor locked heater cores. You can feel and sometimes hear the air bubbles going past your fingers.