Author Topic: Engine temp goes up significantly when lights turned on  (Read 1240 times)

Offline benracing123

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Engine temp goes up significantly when lights turned on
« on: December 01, 2022, 10:39:21 PM »
Hey guys thought I’d bring it to the forums because I’m stumped, I have a digital dash kit that’s been in for some time now and recently when I turn the lights on in the truck the temp will go from 195-220 within 10 seconds I don’t know if I should even think to trust the guage or of my thermostat is fried. If anyone knows anything like this please help


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Offline VileZambonie

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Re: Engine temp goes up significantly when lights turned on
« Reply #1 on: December 02, 2022, 08:59:23 AM »
What gauges are you running? Sounds like you have a poor gauge/body ground.
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Offline benracing123

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Re: Engine temp goes up significantly when lights turned on
« Reply #2 on: December 02, 2022, 09:45:35 AM »
They are the intelirronix guages but I have them all grounded to the motor


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Offline VileZambonie

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Re: Engine temp goes up significantly when lights turned on
« Reply #3 on: December 02, 2022, 11:50:31 AM »
The intellitronix gauges are crap and depending on what ones you got, they have major issues. Nevertheless, make sure nothing is touching and check all connections.
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: Engine temp goes up significantly when lights turned on
« Reply #4 on: December 02, 2022, 06:02:36 PM »
Pretty sure it's electric. Tstats are mechanical.

Does it stay pegged at 220? Or does it fluctuate?
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Offline benracing123

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Re: Engine temp goes up significantly when lights turned on
« Reply #5 on: January 27, 2023, 11:09:57 AM »
Figured it out it is actually a bad ground one of the wires was colored incorrectly


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