1996 Nissan Sentra Engine temp. guage fluctuates between no

235,000 MILES • 4 CYL • FWD • MANUAL
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SCOLLIER
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I recently (like yesterday) had my radiator cap replaced because the old one was defective and boiling coolant out the top. Everything was fine until a couple hours ago, when I noticed my temp guage going from about halfway between cool and hot to almost all the way to the top. In about 15-20 seconds, it would go back down again, only to go back up in another minute or two and repeat the whole process. I've owned this car since 1997 and never had engine cooling problems until now. Any idea what could be causing this?
Feb 19, 2009 at 11:53 AM
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RASMATAZ
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Replace the thermostat and see what happens if it continues come on back. Or get it block and pressure tested.
Feb 19, 2009 at 12:39 PM
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SCOLLIER
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Another thing I noticed after I posted this is that the car was way low on coolant. I put some more in and it stabilized for a while, but then started fluctuating again after I drove a few miles. I'm taking it into the shop in the morning, but it's really starting to look like the head gasket is blown, which I was hoping wasn't the case.
Feb 19, 2009 at 3:25 PM
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RASMATAZ
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  • 75,988 POSTS
When you get it block and pressure tested then you'll know whether its a blown headgasket, cracked head or block.
Feb 19, 2009 at 4:42 PM
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