Nissan Repair: 2002 Altima SL, water geysers, coolant leak

Question
I have a 2002 Altima SL that I have had some trouble with throughout the years. In June of 09 I took the car to the shop and they said I had a cracked head gasket. I took the car to a friend who ran several diagnostic tests and he found no such issues, but replaced several spark plugs and it was running fine once again. The car has a rapid coolant leak and you can hear a "swishing" sound at least once per drive. I have to replace the coolant probably once every three weeks. The heater has stopped working because of this, and I know I need to change the coolant when my temperature gauge begins to rise. When that happens the gauge goes from normal to very hot and back to normal as I'm driving. Do you think I could indeed have a cracked head gasket? I've never had any issues with starting the car or smoking or anything like that, just a broken heater. Also, the shop diagnosed the cracked gasket 18 months ago and I haven't had any major issues. Any ideas??

Thanks,
Jason

Answer
Hi Jason -

You will need to find out where all the coolant is going. If you do not have a leak somewhere, then you must be burning it, in which case you will have to take a compression test.

A simple way to check is fill the radiator all the way to the top. Leave the cap off, and crank the engine. If the water "geysers' up, then the head gasket is probably shot.

If it does not geyser, then take a pressure test on the cooling system to find a leak.

Also remove the thermostat and see if the car runs cooler.

Hope this helps -
aloha
calvin