Looking for help... I have a 99 Tahoe 5.7 4x4... I have owned it for at least four years. In Minnesota, we kinda need some heat sometimes... At least this time of year. Apparently, if I lived in the Carolinas, I would have the 'Top Down' this time of year... uzzled: But, not here... It's below zero degrees right now, and will be for the next week or so. Anyhow, the heater core appeared to be leaking... Swapped out the heater core with an aftermarket, and now I cannot get above 'luke warm'. Even my temp gauge shows about 30 degrees cooler than before the heater core was replaced. After discussing with numerous mechanics (and others), the cooling system has been bled at least 4-5 times, 4 different thermostats have been installed (two are OEM), the heater box has been pulled apart at least 3 times, and I now have cardboard in front of the radiator. The thermostats are 195 degrees. The temp gauge fluctuates between 155 degrees to 180 degrees, and the inside temp fluctuates from cold to luke warm. Does anyone have any ideas? Any GM mechanics have a known reason for something like this? Keep in mind, I have never had a problem with heat until the new heater core was installed... I will also post this in the Tech section of the board. And for all of you southerners... Yes, its true, we can actually 'freeze our A$$ off' in Minnesota... Refer to picture!ou: Thanks, Gil
Gil, just get those little heat packs break em put in shoes and gloves. It will all be over in 2 more months!
I have the same problem in a 93 Ford van except I can't say the engine itself runs cooler or not. I just know that the heat sucks and occasionally at high RPM the heater core makes a weird noise. I narrowed the noise down by crimping the heater hose. Even here we use heat in the winter and the heat in that van sucks even with the radiator totally blocked. Slightly warm is as good as it gets. I'm 99% sure it's the heater core itself since the two problems arose after the core was replaced. It's partially blocked and that's what the noise and lack of heat is all about. It's a backup van now but if I was driving it everyday I'd replace the heater core again. The core came from NAPA and is a POS. I didn't read where you replaced the new core but I'm thinking thats where your problem is.
