I have a 1994 C4 with about 57k on it. The heater doesnt seem to work. I looked to see if the heater core was hooked up, and it is. The A/C works fine but I hardly get any heat. My engine temp ranges from 160-190. I have no clue from here. Can anyone suggest anything.
:seeya

 

I am not sure it still applies to your year car but maybe this might help some:
http://forums.corvetteforum.com/zerothread?id=202649
hope it helps and goodluck

 

I feel your pain. My heater recently stopped working and I had to drive 4 hours in 40 degree weather with the window down to keep the windshield from fogging up.

I took the car into the shop, and the mechanics said nothing was wrong with the heater core. The problem was some electronic components that switch the unit from heat to A/C. It was stuck on AC, so even though the heater core was working, air wasn't being directed through it and inside the car. They had to open up the dash and order 2 new electronic parts that are standard pieces for GM a/c-heater units. I'm waiting for the parts to arrive now.

 

is your fan running good?

 

Chances are your programmer needs fixing. It is an easy check. The programmer is located behind your gas pedal on the firewall. It is black in color, approx 4"x6" wil one bolt connecting it to the wall. It has one electrical connector and a small rubber square of 5 different color vacum lines attached. Remove the rubber connector (bolt in the middle of the hoses) the electrical connector, and the bolt from the firewall. Open the unit and you will see an electrical board. Remove it and turn it over. In the upper right hand corner of the board are two resistors. The board may be discolored where the resistors are. Check to see if they are properly connected to the board. The soldier should be shiny silver. If ther are dull gray or broken, the connection is bad. If you are not good at soldiering, take the board to a TV repair shop and ask them to check the resistor, (i think 120 ohm). If they are good ask them to resoldier the connections (10 second job). If they replace the resistors (49 cents a piece at Radio Shack) it is a two minute job. (It cost me a cup of coffee at the tv repair shop to fix the board, and I walked in cold).
I wooould recommend this fix first. To buy a new programmer is $300.00. The programmer is notorious for going bad - just the resistors.
You may have a problem with the temperature door actuator or the rod connector, but it is highly unlikely. Let me know how you made out.

 

The fan works fine and everything switches from floor and vents just fine, just no heat. I saw the thread about the resistors, but is it the same on a 94 as the older C4's?
:seeya

 

My factory original thermostat was stuck at half open, ran warm in summer and cold in winter, might want to check it. :)

 

This is the first thing I'd check. It's happened to me on 2 of my cars (not the Vette).

 

but the car runs around 180 average all the time. Wouldnt that mean that that wouldnt be an issue?
:seeya

 

Tried putting compressed air through the heatercore? Maybe it's blocked..