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Old 05-21-2018, 10:01 AM   #1
davepl
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Temp gauge reads too high - hack/fix?

My temp gauge reads about 20F higher than actual, and it's at the intake. If it were in the head it'd be more like 40F.

When the thermostat opens at 180, the gauge reads 210.

I'd like to fix that, but the way they work is they read a higher number with more resistance, so I can't add inline resistance, as that'd make it read higher!

I can't think of a way to remove resistance. It's well grounded, that's a grounded as it's going to get!

Anyone know or think of a way to make a gauge read a little lower?
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Old 05-21-2018, 10:38 AM   #2
HO455
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Re: Temp gauge reads too high - hack/fix?

The problem with adding resistance is you will only get the guage to read correct at one temperature and the error above and below that temperature will grow larger the farther the water temperaure gets from the point you corrected it to. I have a great write up on this but it is a PDF and I can't post it as it is too large. The basic idea is correct senders are hard to find. But here is the link to the page. Fortunately I got my copy before the photo sharing greed event occurred which is lucky for me but no so for everyone else. Unfortunately at this point not all of the information is present, but enough of the information is there to maybe help you.

https://www.corvetteforum.com/forums...t-problem.html
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Old 05-21-2018, 10:57 AM   #3
rockyrivermark
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Re: Temp gauge reads too high - hack/fix?

Is the sender and temp guage original or aftermarket? original gauges only read C to H.
I'm assuming you are checking with a IR gun?
if original the replacement sender is
NAPA TS6469, replace it and see if that solves the issue.
if aftermarket google name brand for replacement sending unit.
RRM.
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Old 05-21-2018, 11:01 AM   #4
demian5
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Re: Temp gauge reads too high - hack/fix?

Just like a gas gauge, you know what the temp is (or how much fuel). Just do the math when looking at it.
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