Hello all,

Been noticing that my heat in my 07 H3 hasn't been functioning quite properly..

Basically, when I start up my hummer to warm it up (Wisconsin is cold in December) it wont blow hot air until the thing is moving. When I'm actually on the road it works fine until I come to a stoplight and I'm sitting there for a while the air blows cold and I can smell burning rubber until i start moving again then the heat come back.

I've asked around at work and have gotten various answers from a thermostat to a heater core, someone also told me to check my antifreeze level in the radiator.. The overflow tank was bone dry so I'm going to put some in there when I get home.


So I thought I would ask you gurus on here before I did anything.

 

I am willing to bet that you are just low on coolant.

 

Yes, you need to add coolant, then check periodically. It appears you have a leak. In the meantime, keep that overflow tank up to the full line.

 

is the smell the resistor connector getting hot?
if you run the fan at high the resistors are not in the circuit.
I smell plastic like smell whennon lower speeds and I think I am beginning to have an overheated connector.
still running ok tho.

 

Thanks For All the help, I picked up some Dex yesterday and ill be putting it in when im home.

 

The burning smell is likely from the resister on the blower motor starting to fry. The blower motor is behind the glove box area. Was a common problem in early GMT355s and H3s. Search "burning smell".

 

Definitely, not the weather to check for leaks, (unless you have a heated garage) just keep it full...
I was out driving today in our blizzard conditions(12in.+ today, and high winds), other cars/trucks were sliding all over the place, and I just kept moving along, with no problem.
It was a great day, to be an owner, of a H3!

 

I was out in mine, go to get my daughter at cheering practice and not thinking I go the way I always go which includes a pretty steep hill to go up. I get to the hill cars stuck everywhere so I just go up the hill past everybody. I bet you I was called some choice words.
On the heating front, my old Durango would lose heat and I found the heating core plugged. What I did was back flush it with a water hose and that fixed it.

 

Thanks for all the help, I filled up the radiator and then filled the overfill tank to the little line and the problems persist. it was -14 the past 2 days.. which really wasn't fun to deal with. The only time that warm air will blow is when the truck is moving as I said before.. so I'm not sure what to think. Not very Tech inclined.. so What should I tell my local mechanic to do..?

 

Air pocket or flow problem.. Have you checked the level since you added coolant? When parked does the heat increase when you increase the rpms? When was the last time you had the coolant system flushed? Where is your temp gauge when the vehicle reaches operating temperature? Do you smell coolant, or see a leak?