1998 Chevy Venture 1998 Chevy Venture temp/heat/low coolant

MAJICWEBDESIGN

MEMBER
1998 CHEVROLET VENTURE
6 CYL
2WD
AUTOMATIC
129,000 MILES

I have a 1998 Chevy venture with 129, 00 miles. The temperature gauge goes quickly from cold to hot and back, up and down. I have replaced the thermostat, but that did absolutely nothing. There is no coolant in the oil, and yesterday the service engine soon light came on. The low coolant light also comes on, but does not sty on. The radiator and overflow are both full. I never drained the dex out, I just added some green, so right now it has a mix of both in the system. It does put out a little bit of heat as the temp needle is on its way down, but then nothing as it slowly works its way toward hot again. I have bled from the bleeder valve going into the block, and I did get a little bit of air out, but that still did nothing to help.
I also need to add that, as the temperature gage gets to the hot, the low coolant light comes on. As the gage is on it's way down, the light goes off. Someone suggested to me that it could be the sending switch, but the low coolant light doesn't seem to go with that suggestion. Thoughts?

3 Replies

RACEFAN966

MECHANIC
5,029 POSTS

Ok first off you can't mix the red with the green it will slug up so now you will have to drain and flush the system and put in one color of anti freeze first. Then I would call around to the local parts stores and find one that does a free scan and write down the codes that are found so we can see why the engine light has come on. After writing down the codes have them clear them and get back to me with the codes.