Contour Enthusiasts Group Archives Forums General Troubleshooting Overheating Weirdness

My coolant gauge soars towards the red zone and coincidentally the interior heat plummets to frigid. The cooling fan catches this and the temperature decreases only to repeat the whole cycle...which is ironic given that it's minus 14 right now.

Wondering if this might be:

1) incorrect coolant/water mixture;
2) defective radiator;
3) defective water pump (though this was just replaced)

Other info...I notice a sweet coolant smell (faint) but no puddles under the car. The coolant reservoir is down about .5 litre.

/Eric

It sure sounds like a water pump problem. Did your old pump break the impeller? If so you could have pieces in your system and they could have wiped out your new pump.

Sounds like a water pump... but the intermittence is odd. maybe blockage that is just big enough to fit through thr hoeses. Could be the thermostat sticking closed, but that wouldn't explain the interior heat, i THINK the interior heat system bypasses that completely (thinking back to my water pump replacement.)

It sounds like you have a air locked block from the low coolant level. Fill the reservior a little over the full line and run for a while with the cap off. When the air comes out, the reservoir will drop quickly. Look for dried coolant on the bottom of the new water pump. New pumps seem to weep at the seals either from too much or not enough pressure. Make sure that the upper hose is not soft, as it can collapse and cause problems. The thermostat must be good, and the small hole should be unblocked and at the 12 o'clock position (the hole allows hot water to get up to the thermostats wax pellet and also lets air pass).

Thanks everyone for the advice. I'll try your suggestions when I get back from this business trip and let y'all know what I find out.

/Eric

I just got past the problem that Mystic is having, exact same symptoms of rapidly rising temp without heater output, rapidly falling temp with burst of heat, and repeating.

Problem was water pump (this is a 4 cyl, by the way). My original pump was replaced as a precautionary measure while changing the timing belt, and the one they put in failed after 3 months. The impeller was free-spinning on the pump shaft. Pump was branded/warehoused under the Auto Value name. My mechanic happily replaced it with a new pump under warranty.

I want to thank everyone for participating in contour.org. I was randomly looking on the internet to solve this problem, and the information in your forums led me right to the water pump and back to my mechanic with good information. Thanks again!