Correct operating temperature

[gs14racer]

What is the correct operating temp for the vh?

The gauge on the dash board pegs at hot, but i have an autometer water temp gauge in the top hose on it also and it never goes over 195 typically it stays at 180

The water pump is brand new, and it has a koyo aluminum radiator with two flexalite 2500cfm fans.

Is the dash temp gauge sender possibly fried? I checked the lead on it and there was no corrosion or anything.

[elwesso]

If you're running at 180ish your golden. Most Q run around 180 so you're fine!

Sounds like the lead is ground out somewhere. Does it stay pegged all the time?

[gs14racer]

No it rises as the temp rises, at 150 on my autometer gauge its mid way on the cluster, at 180 on the autometer its right below the H on the cluster at 195 its above the H on the cluster.

[elwesso]

ive been trying to find info on the gauge temp sensor. What I would do in this situation is hook up a sensor from a KA that you know works and see if that makes the gauge run right. may just be the cluster is expecting something different.

I looked in the FSM and I couldnt find any resistance values at various temps we could compare.

[gs14racer]

according to the fsm for the 240sx and the q45 they are the same sender in both cars.

Resistance on the sender is 140 degrees f. 70-90 ohms212 degrees f. 21-24 ohms

[gs14racer]

oh and visually the vh and 240sx sensor are different and are different sizes.

[elwesso]

Where did you find that in the FSM. Also hopefully your not confusing the gauge sender vs the actual coolant temp sensor

Heres a picture of both of them... In green is the gauge temp sensor, in red is the coolant temp sensor. THE ECU only cares about the coolant temp sensor. click to enlarge



I just wonder if maybe the 240 taps off the main one instead of having a separate small sensor.

[maxnix]

If you're running at 180ish your golden. Most Q run around 180 so you're fine!

Thought ideal was 176° F?

[elwesso]

you cant have ONE temperature that the car operates at all times unless you drive in the same manner in the same outside temperature.

The Tstat starts to open at 170F and then will achieve maximum lift at 194F, which is ironic because the ECU goes into "overheat mode" at 195F.

I dont remember what the minimum temp is (im thinking its 160F) when the ECU goes from warm up mode to normal mode, however IMO if you're BELOW 195F at all times you have no reason to be concerned.

[gs14racer]

Yea i got the right one, single wire sensor.

The 240 has a seperate cts for the ecu and for the gauge just like the vh.

Dont know what the heck gives here,

I got some new defi guages coming here shortly, plus ill try swapping out the sending unit for another one from a vh, maybe the autometer is wrong, but for sure my gauge always worked fine before.

[elwesso]

Were those readings for the right sensor (the resistance values you gave)? I want to know where you found that because i searched forever and couldnt find it.

If you have your temp gauge installed right before the Tstat that should be a similar reading to the one on the motor.... I guess the only thing I would do is grab a consult and see what it says.

[gs14racer]

They are in the EL section of the fsm, under meters and gauges, its under thermal resistor.

On the stock VH the sensor is on the outlet of the motor, and thats where i put it on my setup, the autometer temp sensor is also on the outlet.