LS3: Apparently I need three coolant sensors

[ModernMuseum]

Engine: LS3
Radiator: from Prodigy Customs
Gauges: Dakota Digital Series III

To monitor and make all the systems work correctly, it appears that I need three sensors to make all this happen: one sensor for the ECU, one for the fan controller and one for the Dakota Digital gauges.

After some research, it appears that all three use different signals and there is no way to piggy back or combine any of them.

As far as I know, the LS3 only has two locations for sensors, which is at the back of each cylinder head. Am I going to have to tap into the water pump for another sensor? What is your recommendation?

[parsonsj]

II Much had 3 coolant sensors too, though my FAST XFI could have shared the Auto Meter gauge sensor (I didn't learn that until later). I tapped the water pump casting without any problem.

I'd double check the ECU and gauges... if they both use 2 wire sensors, I'd bet they can be shared. I don't know anything about the radiator.

[79 Camaro]

You could use the ecu to turn on the fans. Speartech did that for me.

[parsonsj]

You could use the ecu to turn on the fans. Speartech did that for me.

For sure. I've got a 69 Camaro here right now that works that way. Most ECUs have support for that.

I would add that I like external fan controllers, especially if they support PWM-based speeds where the fans run a slower speed to keep the temp right where it's programmed. Most ECUs just have binary support: either the fan is on or off.

[Z06vette]

I used the stock 02 camaro ECU to run both the fans & turn on one fan when the AC is turned on. It depends on which computer you have, might not work on your setup.

[Mkelcy]

There's also a two output temperature sender from an LS1 Camaro that may work. This was the first link I found with part numbers: http://www.ls1truck.com/forums/lsx-t...re-sensor.html

[68ZClone]

Any reason the fan controller from Dakota Digital would not work?

http://www.dakotadigital.com/index.c...641/prd641.htm

[ModernMuseum]

Ok, in tying up some loose ends, I decided to just use the sending unit that came with the Dakota Digital and install the sensor in the radiator line.

Do I install it in the large 1.5" line or the smaller 1.25" line? I almost pulled the plug on a 38mm adapter (1.5"), but then remembered that I don't know which line I have to install it in!


Here's a decently priced one for $25.

[ModernMuseum]

I guess I should clarify...should it be the upper or lower radiator hose?

[camcojb]

Originally Posted by ModernMuseum

I guess I should clarify...should it be the upper or lower radiator hose?

the upper hose is water returning from the engine to the radiator and would be the one to use.