1999 Chevy S-10 4 cyl Two Wheel Drive Automatic 130000 miles
My 99 S-10 stopped producing hot air from any of the vents when heat control knob is selected to full heat. So I put it on defrost and have selector knobe on cold. I hear the A/C come on and it blowes cold air, then I move selector knobe to full hot and hear a change in air flow to the windshield but no hot air. Disasibled the front part of the dash and looked at the back side of the air selector switches and all of a sudden hot air. This only worked for a few days, right back to cold air. I also noticed a few more days later that the coolent tempreature was lower than normal. So did a complete flush and cleaning of the system with the defrons on and full heat. Also replaced the thermastat as well. Still no heat so again I took the front part of the dash apart and looked at the slector switches and also disconnected the plug to the heat control knobe to see if there were any kind of discolorations. No discolorations, reconnected every thing and my heat is working again. Now three days after I did that I have no heat again. I have also checked both the return line and inlite line to the heater core and both of them are very hot. After I perforned the flush my tempreature gage is still reading low so I am thinking that the tempreature sending sensor is bad. How ever I need to know why I get no heat from any of the vents when I select heat. All the vent doors behind the dash close and open like they are suppost to how ever I have not check the door for the air to flow over the hearter core. Dont know where that is at behind the dash. Please help me, kind of hard to drive when the windshiled will not defrost.
have the same problem?
Thursday, October 14th, 2010 AT 5:08 PM