Get the camaro right and now the blazer is acting up. Well I replaced the heater core 2 months ago and heat was working fine. Today the heater works but barely. The temp gauge reads 130 but goes no higher.

It blows warm heat but not like when I first replaced the heater core. There are no leaks anywhere and the fluid level hasn't dropped since I replaced the hc. Its not overheating so I'm not sure about the thermastat. This is new to me so if anyone has any ideas I willing and able. Oh! Its a 4.3 vortec. Love my 6 shooters.

 

divertor valve not opening up enough, or the coolant just not hot enough. Was in Minot for 2yrs, and experianced it before. maybe try putting some card board in front of grill/radiator to let it heat up faster.

 

The thermostat MAY be stuck open which would cause your heat to be very weak. However, I don't know the normal operating temp of a blazer, so i'm not sure.

 

my 95 blazer has the 195 themostat

 

Funny thing is I took a trip to Raleigh NC this weekend ( about 320 rt) and the temp gague was jumping back and forth. 1 sec it would read a good 180 the it would drop back to 130 or 40. It keep doing this on and off and when it drops back down the truck would hesitate but not cut off. With the cruise control set it never skipped a beat. Now when stopped to get some gas it wouldn't start back up. Shot some starter fliud in there and she fired right up and never cut back off. That issue I think is the cold start injector but not sure. Very weird that I fix 1 (camaro) and the other (balzer) starts acting up. Just lucky it didn't do it while the camaro was down. Now I can park the truck and work on it.