Hi guys,

Wondering if you can help me out. I bought a gorgeous '06 LT with the 3.5 for my wife last month. Only has 103,000kms on it. Having trouble with the cooling system. When it's stopped at a light or otherwise idling, the heater goes cold. I tested it in the driveway, and if she's sitting at 1k, there's no heat; if I increase the RPM's up to 1500, the heat comes back. I've taken it back to the dealer, and they supposedly fixed it (air trapped in the system or something), and it was working fine. However, it's started to do it again. Any advice? I love the car, but I am getting frustrated that we're having problems with a car that we've only had for a month.

Any help would be greatly appreciated!

Thanks
Adam

 

I have a friend who's 3.4 was doing the same thing and, after replacing the water pump, radiator, thermostat and flushing the cooling system for air bubbles, it turned out to be a head gasket. You may want to check your engine's compression to check for vac leaks.

 

My car does the same thing. It is five years old and that has only started the last year. I have to gun it for a few seconds to have the heat turned on. Could be a sticky air-mixer.

 

Air seems to be constantly getting in, did they replace the thermostat or any parts?

 

They didn't replace anything; they performed a bleed on the system, and that was it. I don't care if I have to leave the car there for 2 days or whatever, I just want the damn thing fixed.

 

It's odd because the method of bleeding your car is much different than just opening a valve. Usually takes 3 or more attempts of adding coolant, running the car, adding more, running the car.

 

Anyone that didn't suggest a partially plugged heater core should leave the tools in the box and give up on their attempt to be helpful. Have the heater core flushed out with a mild solvent and warm water. It will be good as new. That is 100% classic plugged heater core symptom.

 

I had the same issue with my 07. I added a lil coolant and it was resolved. I will still get the coolant flushed int the spring.