1G Coolant Temp/Fan switch/Temp Gauge Questions

[Ski Bum]

I just have a few quick questions on the cooling system on our DSM's.

First, Is there a certain temperature at which the radiator fan should always come on (no a/c to factor in)? Mine seems to come on around 200*

Second, I may not even need a n answer for this but how accurate is the factory coolant gauge? When comparing to my logger anything between 192-206* seems to keep the needle at 12 o'clock. Also the needle will go past vertical (clockwise) while the logger shows normal coolant temps. The needle just seems to be all over the place with no real pattern.

Laslty, If any of the coolant temperature probes/switches were going out would there be any symptoms similar to my second question? Or is it one of those things where they either work or dont work?

Thanks in advance.

 

[GVR4592]

The stock fan comes on somewhere between 195-200 degrees.


The temperature sending units for the gauge and the ecu are not the same sending units. If you are getting strange readings from the factory gauge, the sending unit might not be functioning properly. The wires for both sending units tend to get brittle and crack with age. I would check the wiring first. You can't always see the wiring so you might have to pull the rubber boots off to see the cracks.

 

[blackbyrd]

1, The thermo switch on your radiator turns your radiator fan on at 180-190*F.
2, The stock gauge is somewhat accurate. How does it just jump around, what specifically does it do while your logger says?
3, It could possibly be a sending unit/sensor, or faulty wiring but you'll have to describe the problem better.

EDIT: You beat me to it, I should've refreshed. Anyways in my shop manual it says the thermo switch on the radiator comes on at 180-190.. Where did you get your readings??

 

[Ski Bum]

My fans do not come on until after I see 200* on the logger, usually 203*. I have since wired an overide switch so I can run the fans whenever needed since the sensors/switches arent doing their job.

The factory gauge doesnt really seem to coincide with the logger readings. Sometimes if the factory gauge is at full vertical or even just to the left of vertical the logger will read 200*+ other times when the needle is in the same position the logger will read in the low 190's. Also since I have installed the switch the needle will immidiately move to the left slightly when I open the switch. Not sure why there.

 

[GVR4592]

EDIT: You beat me to it, I should've refreshed. Anyways in my shop manual it says the thermo switch on the radiator comes on at 180-190.. Where did you get your readings??

Datalogger, Dsmlink, Autometer gauge, and AEM all say around 195-200 degrees when the fan comes on. Same thing with my brothers 1g and my cousin's Galant.

 

[blackbyrd]

Do you think thats just a difference in temps because of sensor location? or maybe just different switch, age/wear of thermo switch?

Either way, turning on at 200 isn't a bad thing to be worried about, as it sounds from GVR^^. I do however always run with both of my fans running, just to keep temps down as much as possible. So that's a good thing!

 

[Ski Bum]

Is it worth replacing all 3 of the switches and sensors or are they ok as long as they are still turning on?

Any ideas on the correlation issues between my datalogger and factory temp gauge?

Also i've been thinking it would be nice to be able to have the fans run for a bit after the car has been turned off inorder to avoid boil over. Aside from those stanalone fan controllers is there a way to keep the coolant circuits energized so they come on like during normal operation?

 

[fwdturbobov1996]

You said you have your fans wired to a switch? Just turn the key to acc and flip the switch and it will run the fans. Just be careful and dont walk off ha

 

[JwpRider]

By experence, I recalled the havoc that a bad (or the wrong) coolant temperature sensor will cause a DSM. I have been looking for the following info for a while as to share it with our wonderful membership. I found it (again) on ECM Tuning's web site. (So, Thanks go to them!)


Enter ECU Learn Mode :: 180F (82C)
Coolant Fan ON LOW :: 210F (99C)
Pull 1 degree timing :: 206F (97C)
Pull 2 degree timing :: 224F (107C)
Coolant Fan ON HIGH :: 224F (107C)
Enter Open Loop Mode :: 228F (109C)
Default Coolant CEL :: 235F (113C)
A/C Override :: 240F (115C)

I have heard that some 2G's have different sensors..they fit, just provide the wrong values to the ECU...this needs to be verified...by a 'wiseman'...

 

[TGST90]

Ok, I need help with my problem...my temperature gauge isn't working and I don't know if it's my sensor or wiring, How would I found out which one it would be?