Strange temperature gage fluctuation
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Strange temperature gage fluctuation
Hey everyone,
I've owned my '92 7.3 for six or seven months now and have loved it. It's a great truck. One issue that I've noticed is that when cruising down the road, the temp gage usually rests around the "n" or the "o" on "normal", which seems correct, however sometimes it will drop to just above the first line for a bit and then come back to where it should be. It does this pretty rapidly (all within a few seconds), maybe too rapidly for a real temperature change. I've never seen an engine cool down and then heat up that fast. Does this sound like a crummy factory temp gage or a sending unit? I would say thermostat, however it just seems like the water would be making 30 degree temperature changes in just a matter of a couple seconds, which doesn't seem possible.
I did flush the cooling system a few months ago, install a new copper/brass radiator, and fill it with fleetcharge. I didn't replace the thermostat, as I probably should have.
Thanks for any help,
Dan
I've owned my '92 7.3 for six or seven months now and have loved it. It's a great truck. One issue that I've noticed is that when cruising down the road, the temp gage usually rests around the "n" or the "o" on "normal", which seems correct, however sometimes it will drop to just above the first line for a bit and then come back to where it should be. It does this pretty rapidly (all within a few seconds), maybe too rapidly for a real temperature change. I've never seen an engine cool down and then heat up that fast. Does this sound like a crummy factory temp gage or a sending unit? I would say thermostat, however it just seems like the water would be making 30 degree temperature changes in just a matter of a couple seconds, which doesn't seem possible.
I did flush the cooling system a few months ago, install a new copper/brass radiator, and fill it with fleetcharge. I didn't replace the thermostat, as I probably should have.
Thanks for any help,
Dan
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.Thanks,
Dan
Lead Driver
Joined: Apr 2008
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The one you want is around $10 the idi has 3 and it can be confusing which one theyre giving you. Mine was doing the same thing kinda, would just peg to hot and back to normal all within a few seconds. Then i noticed it was staying right on N when it was getting hot. Just picked up my new one yesterday, not as easy to get to as you would think, at least with serp.
Logistics Pro
Joined: Apr 2005
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^^^ What those guys said. 
Here's a pic, courtesy Dave S:
https://www.ford-trucks.com/forums/8...ml#post8025323
Here's a pic, courtesy Dave S:
https://www.ford-trucks.com/forums/8...ml#post8025323
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Sorry for the late response. I haven't had much of a chance to look at it yet, but this weekend it's on my to do list, once again. Thanks for all the help. I think this is the most helpful forum I've been a part of.
Dan
Dan
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