Temp Sending Unit
#1
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Year: 1996
Model: Cherokee
Engine: 4.0 I6
Temp Sending Unit
Just replaced the temp sending unit on my '96 XJ (it's located on the rear of the head in my model). Thought the old one might have been giving me a false reading, but the new one shows temps almost in the red shortly after start-up. I know the thing is not getting that hot that quick. I was sure to order the one which is meant for the temp gauge and not the light. Maybe I got shipped the wrong part? Anyone else ever had this problem?
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Richard Esparza (10-27-2020)
#2
CF Veteran
Check the ground from your engine block to the negative terminal of your battery. Check all other grounds for that matter. Bad sensor readings are often from a bad connection.
#3
There is no ground wire for the temp sender.The sender itself is the ground.It's a one wire unit.Try putting di-electric grease in the harness,it will give you a good connection.If that don't work then try another one.The new one may be bad.Go to Advance,they are $9.99 there and I've had no prblems with mine.
#4
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Right, and the engine block has to be well grounded for the ECU to pick up the resistance of ground from the engine block to the sensor. Or in this case the gauge in the dash, rather than the ECU. The sending unit for the gauge in the dash is a variable resistor dependent on the temp of the coolant in the cylinder head. The coolant temperature sending unit which the computer uses to control fan speed and fuel mixture is a two-wire connection.
Last edited by alpine.adrenaline; 08-02-2010 at 08:59 AM.
#5
Right, and the engine block has to be well grounded for the ECU to pick up the resistance of ground from the engine block to the sensor. Or in this case the gauge in the dash, rather than the ECU. The sending unit for the gauge in the dash is a variable resistor dependent on the temp of the coolant in the cylinder head. The coolant temperature sending unit which the computer uses to control fan speed and fuel mixture is a two-wire connection.
#6
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Year: 1996
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Engine: i6 4.0
the sending unit has nothing to do with gauge. you needed the coolant temp. senser at the front of motor in front of tstat. try this for location
Coolant Temperature Sensor (CTS) Resistor Trick
Coolant Temperature Sensor (CTS) Resistor Trick
#7
the sending unit has nothing to do with gauge. you needed the coolant temp. senser at the front of motor in front of tstat. try this for location
Coolant Temperature Sensor (CTS) Resistor Trick
Coolant Temperature Sensor (CTS) Resistor Trick
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#8
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Year: 1996
Model: Cherokee
Engine: 4.0 HO
THe one in the front is for the computer.
The one in the back is for the gauge. Yes they may have sent you the wrong one. How does your coolant look? Have you done the obvious? TStat etc? When I swapped clusters the idiot light switch was still in it and the gauge pegged out.
#9
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Year: 1996
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Here's another thing... The new sending unit's nut is wider than the old one. When I put it in, it almost rubs against the valve cover... really a pain to get screwed in. I don't guess the valve cover could be heating the upper portion of the sending unit in a way that makes it read too high could it? (Anything is possible by this point I guess)
#10
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Year: 1996
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Engine: 4.0 HO
OK here it goes.
I bought mine at Autozone. Its made by Standard. Part number is TS334. Theres also another number on the box M10075. YES they are a PITA to get to! I doubt the valve cover would do anything. Is the wire connector black or white? The one for idiot lights are black. Gauges White. I had to do my gauge swap by learning. So thats why when I plugged the gauges in with the idiot light switch the temp spiked to max. When in doubt have the radiator rodded. Ive seen water pumps practicaly missing impellers too.
Last edited by R Cannon; 08-03-2010 at 12:37 PM.
#11
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Year: 1996
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I bought mine at Autozone. Its made by Standard. Part number is TS334. Theres also another number on the box M10075. YES they are a PITA to get to! I doubt the valve cover would do anything. Is the wire connector black or white? The one for idiot lights are black. Gauges White. I had to do my gauge swap by learning. So thats why when I plugged the gauges in with the idiot light switch the temp spiked to max. When in doubt have the radiator rodded. Ive seen water pumps practicaly missing impellers too.
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Glad I saw this thread. I just bought an aftermarket gauge to replace my dummy light. I would have completely removed the wrong thing thinking it was the temp sending unit. You said it was at the back of the block close to the valve cover. I was like "wait...no it's not" Then sadly I found it way back there. lol.
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Year: 1996
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Oh man.
I hope you can get to the problem. When in doubt take the T stat out and Quadruple the flushing. Good Luck! I flushed mine 6 times. The head could have gunk in it. Trust me it happens
#14
temp sending unit harness
Anyone have luck finding a new harness? Mine was fried/burnt to a crisp and the wire fell off. Having trouble locating a new harness. Has anyone jerry rigged one?
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0