Volkswagen Repair: 98 VW beetle, coolant level, radiator flush

Question
at the beginning of the summer i was having problems with my car over heating when I'd get stuck in traffic. i had the temp sensor and fan switch replaced and also had a radiator flush and the problem was solved. recently when I've gone to get in my car (after its been sitting out all night or for like 5 hours in the cold, i live in Seattle and its pretty cold here) as soon as i turn on my car the blue cool light comes on then after about three seconds it turns to red so i turn off my car immediately turn it back on and it goes away. its been doing that for about a week. now today i was stuck in traffic and my car started over heating i pulled over did my trick of turning off my car and turning it back on and it went away. whats wrong with my car. is it oil? or low coolant? please help :(

Answer
Hi Brittany;
The coolant reservoir bottle has a problem.  That's the first thing.  The coolant level sensor is in it.  Also, if you are overheating, there must be another place that coolant is escaping, and where air bubbles are getting into the system.  I would guess that the "coolant flange" is seeping fluid out, and air in.  I live in the Everett area, so I know about the nights lately.  The level sensor is what turns on the red light.  I don't know why it would then turn off, but it is probably related to the reservoir.
Hope this helps you, Brittany.  Good luck.  Let me know if I can do more.