2002 chevy blazer heat problem

paxlineman · 01-29-2010, 04:47 PM

ok as it says in the title its a blazer with the 4.3l engine. the problem is that the heat is not warm its almost cold. it blows nicely but not warm . anyone have any ideas on how to fix this dilema of mine.

TomJenks · 02-16-2010, 02:09 PM

sounds like a plugged/partially plugged heater core. The cheap trick to do is take the hoses off and flush the heater core both ways with a garden hose. Usually that takes care of it most the time. How often do you change your antifreeze? Dex-Cool is notorious for causing cooling problems if it has never been changed. The expensive way is to replace the heat core(dash removal= big $$$).

**shane96ranger** · 02-17-2010, 07:50 PM

Are you sure the cooling system is full? No heat is sometimes an indicator of low coolant level.

john112deere · 02-17-2010, 08:00 PM

Starting with the easiest to check, does the temp gauge come up like it should?

After that, see if both hoses running into the heater core (under the hood) are hot, after the engine is up to temp. If not, plugged core. If they are, blend door issues, maybe. Not sure how the blend door works on a Blazer, though.

*Paxton, huh? I grew up in Holden.

MountainMike · 02-19-2010, 12:51 AM

Could be your thermostat or also your operating temperature. Do you run a winter front? If you don't your engine is using all required heat just to keep it self warm which makes a noticeable difference in cabin heat.

My experience comes from living north of 60

01-29-2010, 04:47 PM	#1
paxlineman Member Join Date: Feb 2009 Location: Paxton, Ma Year: 2001 Make: Ford Model: Ranger XLT Engine: 4.0 Class: 4x4 Used For: everything Posts: 308 Rep Power: 9 iTrader: (2)	2002 chevy blazer heat problem ok as it says in the title its a blazer with the 4.3l engine. the problem is that the heat is not warm its almost cold. it blows nicely but not warm . anyone have any ideas on how to fix this dilema of mine.
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02-16-2010, 02:09 PM	#2
TomJenks Junior Member Join Date: May 2009 Location: N.E. Kansas Year: 1992 Make: Ford Model: Ranger Engine: 4.0 Class: 4x4 Used For: haulin junk Posts: 42 Rep Power: 9 iTrader: (0)	sounds like a plugged/partially plugged heater core. The cheap trick to do is take the hoses off and flush the heater core both ways with a garden hose. Usually that takes care of it most the time. How often do you change your antifreeze? Dex-Cool is notorious for causing cooling problems if it has never been changed. The expensive way is to replace the heat core(dash removal= big $$$).
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02-17-2010, 07:50 PM	#3
shane96ranger \----===FoMoCo===----/ Join Date: Oct 2009 Location: Utah Year: 1997 / 1989 Make: Ford Model: F150 XLT / Mustang GT Engine: 4.6 Triton / 5.0 Class: 4X4 / Hot Rod Used For: Everything / The war on imports Posts: 7,751 Rep Power: 62 iTrader: (2)	Are you sure the cooling system is full? No heat is sometimes an indicator of low coolant level.
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02-17-2010, 08:00 PM	#4
john112deere Junior Member Join Date: Dec 2007 Location: central Vermont Year: 1997/2009 Make: Ford Model: Ranger Engine: 2.3 / 4.0 Class: 4x2 / 4x4 Used For: whatever I happen to need to do Posts: 72 Rep Power: 11 iTrader: (0)	Starting with the easiest to check, does the temp gauge come up like it should? After that, see if both hoses running into the heater core (under the hood) are hot, after the engine is up to temp. If not, plugged core. If they are, blend door issues, maybe. Not sure how the blend door works on a Blazer, though. *Paxton, huh? I grew up in Holden. __________________ 1997 Ranger Supercab XLT, 4x2, 2.3 4-cyl, 5-speed, 4.10 gears. More or less stock, 260-odd thousand miles 2009 Ranger Supercab XLT 4x4, 4.0 V-6, 5-speed, 3.73 gears.
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