On the first cold day of winter (below freezing) our van temp gauge pegged out into the redzone and the warning light came on. However, the heater was not blowing warm air at all.
We took it in to a local shop and they could not repeat the problem. Carbon dioxide test came back negative. The shop did not want to change the thermostat because they had no idea what was wrong with it.
I picked the van up after work on a Friday and it touched the redzone on the way home. I had read something about there being two relays for the fans, so I tried turning the air on to override one of the relays and the temp started to drop immediately. However, still no heater. Monday got up early to fill the van up and check it out, it never overheated on the way to the gas station, but came very close. Still no heater.
I can find a lot of complaints about Chevy Ventures like this on the interent, but no one has posted a solution.
Monday, January 28th, 2019 AT 6:20 PM