Coolant temp going crazy
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More Turbo
Joined: Mar 2010
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From: Bakersfield
Coolant temp going crazy
My coolant temp readings have been acting funny. It was getting into the 170s so I changed the thermostat. I thought it fixed the problem but sometimes I still get readings in the 170s. Sometimes it will jump 10 degrees out of nowhere. Cold soak temps are equal and close to ambient temp. When the ECT is in the 170s my EOT is 185-190. Other times ECT will be 190 and EOT 195. I am not sure how to account for temps being all over the place. Maybe ECT sensor is bad or the new TSTAT is. Highest difference in ECT/EOT 22 degrees. When ECT reads 190s there's only 5 degrees difference. Any ideas?
Lead Driver
Joined: Oct 2010
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From: Ouray, CO
My coolant temp readings have been acting funny. It was getting into the 170s so I changed the thermostat. I thought it fixed the problem but sometimes I still get readings in the 170s. Sometimes it will jump 10 degrees out of nowhere. Cold soak temps are equal and close to ambient temp. When the ECT is in the 170s my EOT is 185-190. Other times ECT will be 190 and EOT 195. I am not sure how to account for temps being all over the place. Maybe ECT sensor is bad or the new TSTAT is. Highest difference in ECT/EOT 22 degrees. When ECT reads 190s there's only 5 degrees difference. Any ideas?
You also have to purge any air out of the coolant system by getting
the engine up to temps for a while, letting it cool and re-filling (if necessary) the degas bottle.
(you might need to check again in a day or two)
Your temps sound pretty normal. Until the engine is fully warmed up ECT and EOT temps
are "warming up" at different rates so don't sweat the deltas then.
Once the ECT reaches 190* the EOT will go higher - that is when
the delta is watched. At highway speeds for 20 minutes,
On flat terrain (fully warmed up) the delta should be < 15*.
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More Turbo
Joined: Mar 2010
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From: Bakersfield
Before doing the STAT I drained 2 gallons of coolant. When done, put it back so should be ok there right?
As far as coming up to operating temps that is when these temps have been taken. Sometimes it comes up to 180s then back to 170s. This morning going to work ECT and EOT wouldn't go past 170s.
As far as coming up to operating temps that is when these temps have been taken. Sometimes it comes up to 180s then back to 170s. This morning going to work ECT and EOT wouldn't go past 170s.
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Joined: Jul 2005
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From: Millersville, MD
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More Turbo
Joined: Mar 2010
Posts: 599
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From: Bakersfield
Going to check this today. Anyone know how hard it is to get to the sender?
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Fleet Owner
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From: Spanaway
You also may want to check the plug and wires.
In the plug check for corrosion. Clean and put on some
dielectric compound before reassembling.
The wires should be checked for chaffing.
The sensor could still be bad.
Sean
In the plug check for corrosion. Clean and put on some
dielectric compound before reassembling.
The wires should be checked for chaffing.
The sensor could still be bad.
Sean
FTE Legend
Joined: Jul 2005
Posts: 65,938
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From: Millersville, MD
There no way that it going to go to that temp right after start. Did the engine SOUND like it was at idle? Did you have black smoke POURING out the exhaust?
You also should have started a NEW thread instead of horning in on the original poster. Request that one of the moderators move it for you.
You also should have started a NEW thread instead of horning in on the original poster. Request that one of the moderators move it for you.