Temperature gauge different from ecu reading for coolant

[96z71sas]

Ok I changed my sending unit for my water temperature gauge the one on left side the old one only went up to 100 now it reads 220 and hotter when I climb a hill my scan tool says the ecu reads 195 there is 2 different sensors I changed both sensors and the thermostat only thing I can think is that the new sending unit for gauge is wrong I’m going to get a new one and throw a water pump on too did anybody ever have this happen any hemp would be great thanks oh it’s a 96 k2500 5.7 vortec

 

[Caman96]

the old one only went up to 100

now it reads 220

Maybe it was the gauge all along?

any hemp would be great

You’d have to smoke an awful lot.

 

[96z71sas]

Maybe it was the gauge all along?

You’d have to smoke an awful lot.

Thats the next move but why would one be 100 and new one 220 and it goes hotter when you drive up hills but then goes down the gauge does a full sweep btw

 

[Caman96]

Thats the next move but why would one be 100 and new one 220 and it goes hotter when you drive up hills but then goes down the gauge does a full sweep btw

IDK, but your scan tool confirms it’s at 195° and it’s getting that information from the sensor, so that tells me the sensor is good. Which leads me to believe it’s the gauge.

 

[96z71sas]

IDK, but your scan tool confirms it’s at 195° and it’s getting that information from the sensor, so that tells me the sensor is good. Which leads me to believe it’s the gauge.

There’s one for ecm and one for gauge I replaced both and thermostat just cause I did a ground test the gauge goes full sweep no problem I’m going to do water pump and new sending unit for gauge if they are still reading different it’s the gauge I’ll let ya know thanks! I believe these stock gauges have oil in them that goes bad idk you ever hear of that

 

[PlayingWithTBI]

I have a Dakota Digital dash with their 2 wire temp sender to gauge. I've found throughout different conditions and speeds, the dash gauge is almost consistently 10° higher than what the ECM sees. Keep in mind the dash sender is in the head reading hotter than the one next to the T-Stat which is in the water jacket.

 

[Schurkey]

Yup. Not uncommon for the gauge sending unit, and therefore the gauge to read hotter than the temp sensor and ECM.

The gauge sending unit is picking up radiant heat from the exhaust manifold in addition to the heat in the coolant. I've heard +10 to +15 degrees F is fairly common.

 

[96z71sas]

Yup. Not uncommon for the gauge sending unit, and therefore the gauge to read hotter than the temp sensor and ECM.

The gauge sending unit is picking up radiant heat from the exhaust manifold in addition to the heat in the coolant. I've heard +10 to +15 degrees F is fairly common.

I have headers too that might be why I know it should be around 210 but it goes higher than 220 when I go up hills I’m going to throw a water pump on too thank you for help