Fluctuating Engine Temp
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Joined: Apr 2016
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From: KY
Fluctuating Engine Temp
So I feel in the past my engine temp would stay steady at 201 if I remember correctly. I just noticed that it has started to fluctuate from 198 up to 208. My truck is a 2016 3.5tt with about 42k miles. I feel like this is odd. Does anyone else have this issue and should I be concerned about it? Thanks
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Joined: Jun 2017
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Those numbers don’t seem to be terribly out of the typical range for these trucks. It does seem odd that it’s moving from low to high and back again. You still have a power train warranty so this maybe something to chat with your service advisor about, but my first step would be to double check the coolant level and then start checking all the lines to make sure I didn’t have a leak. Start at the radiator, check pressures, then start working your way through the system starting with the thermostat.
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Entirely normal. Mine fluctuates between 199 and 209. Ford wants to keep the engine hot... engines are more efficient at higher temps. You've got variable shutters in the grille that can go to any value between open and closed - but closed is more aerodynamic, thus more fuel efficient. The fans are controlled, but running them means more engine load (via the alternator) and more fuel burn, so Ford wants those off.
If you see numbers above 230, start getting concerned. The motor will start to limit power output and protect itself north of 240.
If you see numbers above 230, start getting concerned. The motor will start to limit power output and protect itself north of 240.
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Joined: Aug 2017
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From: Canada
10 degrees fluctuation is normal... It will get hotter at traffic lights, and get cooler on the freeway... Lots of factors to consider here, but a small fluctuation is normal.
Last edited by Eduskator; Apr 23, 2018 at 02:06 PM.
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From: Memphis TN
I'd say that's well within normal and I'm guess you're reading this off either a display or using some aftermarket meter?
As you wouldn't see that in the needle movement of the standard gage. Or it would be very hard to notice.
As you wouldn't see that in the needle movement of the standard gage. Or it would be very hard to notice.
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Joined: Jan 2012
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From: Lakeville, MN
Some fluctuation is normal, and the temps you are reporting are definitely in the normal range. This is part of why automakers have dampened the motion of the needle around normal temperatures - folks see movement and get concerned, but in reality it does fluctuate some.
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From: Memphis TN
That temp swing is normal and if you're not used to it don't be so surprised if your "normal temp range" expands a lot this summer. Ie when it's 90 outside and you sit at a light you might well see 220 on the gage - and watch it dip back to 210 once you get going around 45-50 MPH.