princej

thats not true.

there is a fix to this problem. after my heat stopped working, it was extremely frustrating dealing with the 2 local dealers in my area, then finally I went out of province to get this issue fixed once and for all. and i can honestly say, this issue of no heat has not come back.

this is now my 5 winter with the uplander, 3rd winter after the repair. the heat is perfectly fine.

your gm dealer is either lazy or incompetent. it came from the factory with good heat. its logical to assume, if there are no head gaskets leaks or other mechanical problems with the engine, the heat should be there like it was when it was new.

make sure your coolant overflow bottle is full to the max line,. and add coolant to the rad cap. (on the left of the engine)

sambo43616

we have tried the same thing you all did and then a friend of ours who is a mechanic told us to get a new radiator cap and low and behold we have had heat since. i can now start my car in this 20 below weather and get into a warm car. also make sure your coolant is full and add coolant to the rad cap.

lboyum

This Sunday my husband turned on the van to warm it up before church. He turned all the fans off while the engine was warming. When he turned the fan on he got a burst of antifreeze smell. I have never smelled it before because I always leave the fan on when it is warming up. The temp of heat still drops when I come to a stop or slow down in traffic. GM offered me a 30,000 mile warranty on the HVAC system with no deductible so I brought it to another GM dealer to have them look at it. It is at the shop hopefully getting fixed today. My husband suspects there is a tiny leak in the heater core which is allowing air into the system hence the heat drops when I come to a slow. I really hope they can fix it and not just tell me it is normal for this car to do that. It would be nice to have heat at slower speeds before summer is here. If the shop can't fix it I will certainly try the radiator cap.

capucine

The radiator cap could be your problem as mentioned earlier. Is your van extended?

lboyum

My van is the extended version (I think 2008 uplander LT). It has 74,000 miles on it. I just heard back from the dealership and they are suspecting a slow leak in the head gasket. They are putting pressure in different places to try and figure it out. I really hope they can get to the bottom of it. They said if it is leaking it is a very small, slow leak that is allowing air to get into the system.

edwalk1

There is certainly a problem with the LT ext vehicle(mine 2008 w/79k miles). I live in Florida and the weather got into the low 50's in the last days. I can deal with it, but I was warming the van to take my girls to daycare. It had been 25 minutes and it was like I never started the car. Until I started driving, only then did I start to feel the warm air start blowing.

lboyum

I just learned that my van had a puddle of antifreeze under it after they let it sit with pressure on it over night. It for sure needs a new water pump and they still suspect it needs a new head gasket. Glad I bought that extended warranty right now. Disappointed it has taken 2 months of it being at the shop to finally get someone to listen and figure out what is really wrong with the thing. We will see if this fixes the heat issue.

sambo43616

lboyu kep me posted like i said the new radiator cap really worked but we dod not have leaks . hope they can fix it

lboyum

They replaced the water pump on my van and highly suspected it still needs a new head gasket, but they wanted me to test drive it and let them know how the heat was working. When I picked it up on Thursday I had the most amazing heat I have had in a really loooooong time. I actually had to turn the temp down. Yesterday I drove it and it started acting like it used to. It isn't quite as bad as before the water pump replacement, but knowing how it heated the day before I am bringing it back so they can look more closely at the head gasket issue. It appears the heater, because of the design (high placement in the cooling system), acts as an indicator for the tiniest leak/irregularity in the cooling system. Air gets into the system and settles in the heater core when the engine slows hence the decreased heat at idle and slowed speeds. I never had puddles of coolant under my van. They only discovered the leak after leaving pressure on it over night. I am no mechanic. I am just speaking from my own experience and hours of staring at diagrams of this vehicles cooling/hvac system and reading peoples experiences. Thank you for the advice on the radiator cap. I will get a new one. It can't possibly hurt.

lboyum

My van is back home after being repaired and it is putting out heat, a vast improvement from when I started this journey with repeated visits to the mechanic. The mechanic sat down in the van with me and told me when I am warming the van up, to get optimal heat I should put the A/C on and turn the rear fan on wide open. Have the temp setting as high as it will go. He said by turning it to A/C it is taking cabin air and recycling it past the heater core. In other words it is taking warm air and making it warmer instead of taking outside air and trying to warm it up. He said it will not harm the car to do this, but the windows may fog up and when that happens to switch it to the normal heat settings. I know it sounds crazy to turn the A/C on when you want heat, but it actually works. It puts out much more heat that way. I am satisfied with the way it is right now. It doesn't drop its temp when I go to make a left turn or blow cold air at idle. It has been very frustrating to deal with GM and two different dealerships. For you others experiencing heat problems my advice to you is to look for leaks in the cooling system and make sure there is no air that has gotten into the cooling system. If your mechanic won't listen to you as my first one did, go to another. The second mechanic finally put pressure on the cooling system which discovered leaks. By the way they checked my radiator cap and it held pressure so they said I did not need to replace it.