AMC Eagle Den Forum

The Shop => Question and Answer => Topic started by: Kippnidaho on March 06, 2013, 08:17:06 PM

Title: Water Temperature Sending Unit
Post by: Kippnidaho on March 06, 2013, 08:17:06 PM
My temperature guage is not working properly and it appears the sending unit is where the issue is.
My question is why is it so expensive? Any other unit is 10 - 25 bucks. I am finding the cheapest price online is 46 bucks. Is there something special about the unit. Can I use something else?
Sorry I am such a cheap skate. But hey every buck counts.
Thanks
Title: Re: Water Temperature Sending Unit
Post by: eaglefreek on March 06, 2013, 08:20:33 PM
The one for $46 is for the computer or emissions stuff. The one for the gauge is this one http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_coolant-temperature-sensor-bwd_3999645-p?searchTerm=coolant+temperature+sensor
Title: Re: Water Temperature Sending Unit
Post by: JayRamb on March 06, 2013, 09:40:25 PM
My temperature gauge runs cool. I don't know if it is the gauge itself or if it is the sending unit. I don't want to take the dash apart for I don't really think it is the gauge. Maybe the Sending Unit?!
Title: Re: Water Temperature Sending Unit
Post by: Kippnidaho on March 06, 2013, 09:46:45 PM
My 83 SX/4 has the two wire sending unit. How would I rewire for the gauge style sending unit.
Title: Re: Water Temperature Sending Unit
Post by: Amc1320 on March 06, 2013, 10:07:39 PM
I have had dozens of AMC's never had one that showed the temp much above the "C" on the gauge

I think that's the normal range for these cars, if it gets to half way up I would know I had a problem

Rob
Title: Re: Water Temperature Sending Unit
Post by: eaglefreek on March 06, 2013, 10:26:20 PM
Quote from: Vince on March 06, 2013, 09:46:45 PM
My 83 SX/4 has the two wire sending unit. How would I rewire for the gauge style sending unit.

You sure? The one for the gauge is located in the back of the cylinder head. Where the red circle is on this photo I snagged from the net. The two wire one is in the intake manifold and has nothing to do with the gauge.
(http://www.jeepforum.com/forum/attachments/f12/53258d1219469814-ultimate-coolant-temp-sender-sensor-thread-once-all-temp-sending-unit-sensor.jpg)
Title: Re: Water Temperature Sending Unit
Post by: vangremlin on March 06, 2013, 10:38:34 PM
Quote from: JayRamb on March 06, 2013, 09:40:25 PM
My temperature gauge runs cool. I don't know if it is the gauge itself or if it is the sending unit. I don't want to take the dash apart for I don't really think it is the gauge. Maybe the Sending Unit?!

Like Amc1320 said, my runs cool also, barely above the C.  You can test the gauge by grounding the sending unit wire, the needle should go all the way to top if you do that.
Title: Re: Water Temperature Sending Unit
Post by: JayRamb on March 06, 2013, 10:49:17 PM
From my understanding the Temperature Sending Unit with the two wires on the manifold...registers with the computer then to the gauge as well. Am I wrong with this one?
Title: Re: Water Temperature Sending Unit
Post by: carnuck on March 06, 2013, 11:26:23 PM
There is a resistor wire between the sender and the harness. I took mine out and got a more accurate reading
Title: Re: Water Temperature Sending Unit
Post by: eaglefreek on March 07, 2013, 07:46:31 AM
Quote from: JayRamb on March 06, 2013, 10:49:17 PM
Am I wrong with this one?
If you have a 258, yes you are mistaken. I removed the 2 wire one in the manifold along with the computer and my gauge works fine
If you have a 4 cyl. I have no idea.
Title: Re: Water Temperature Sending Unit
Post by: skuhler on May 20, 2014, 08:10:02 AM
You removed the one in the manifold?  Did you cross the wires or leave them open?  I've bypassed the computer using the ECM Test bypass, but my gauge on the dash reads C also. 
Title: Re: Water Temperature Sending Unit
Post by: eaglefreek on May 20, 2014, 08:20:38 AM
Quote from: skuhler on May 20, 2014, 08:10:02 AM
You removed the one in the manifold?  Did you cross the wires or leave them open?  I've bypassed the computer using the ECM Test bypass, but my gauge on the dash reads C also.
I'm running a Motorcraft carb and  removed the computer and most of it's wiring.
Title: Re: Water Temperature Sending Unit
Post by: BenM on May 20, 2014, 10:00:02 AM
If the sender is accurate and the thermostat is accurate at 195º the gauge will run from the bottom of the green band to the middle of the green band. If you have a 180º or less thermostat your car will run cold. You could also have a bad thermostat.
Title: Re: Water Temperature Sending Unit
Post by: carnuck on May 29, 2014, 08:56:19 PM
Try grounding the wire going tot he head behind the carb. If an aftermarket sensor is used, AMC used to add a short resistor wire to the line.