Just bought a 2006 Trailblazer, & when the heat is on there is an odor of antifreeze coming through the vents. I checked all the hoses & there doesn't seem to be any leaks. An advice what might be causing this?

 

I saw your post in the general tech area too...
Its likely the heater core, think of it as a small radiator that has a fan and uses the engine heat to warm the people compartment... just like the larger one in the front of the engine it can develop leaks, more often then not its poor maintenance of the cooling system that leads to leaks...but its not uncommon for them to fail after so many years of use...

 

I have to leave town this weekend, is it in danger of over-heating if I drive it for about 400 miles?

 

Its going to depend on how badly its leaking...
there are options, one is to by-pass the heater core by coupling the two hoses together but that will leave you will no heat...
You can probably just keep an eye on the over flow tank and make sure its never empty by keeping it filled between the hot and cold lines and you will be fine until you get back in town to fix it....

the heater core is probably about $70 or less, its the work involved in getting the old one out and the new one in and everything reassembled...some vehicles are easy some not so much...

 

Thanks for the help!

 

I will also add that if you have to add anti-freeze, be sure to use the correct kind... mixing green antifreeze with the newer style orange or red kind can make a cottage cheese like solid and it can clog the radiator and any other small passages in the cooling system....this will cause over heating...

 

Thanks. Does $900 including labor sound about right for replacement?

 

Usually you end up with a coolant bath on your floor.

Depends on where you go. I was quoted near this amount on another car - and being a poor kid working at mcd's, this was my very first car repair on my own.

It is mostly labor intensive (but pretty damn simple) - Generally - you remove a bunch of crap from the interior panels down below, unhook the hoses in the engine bay from underneath, and replace. Reinstall the panels, and fill the coolant up, and bleed the system.

Replacement parts are usually lifetime guarantee - because they use metal pipes instead of GM plastic!!! Yes - the GM plastic eventually cracks and blows.