Engine temp too low ? (pics)

[nbesheer]

Okay so i was wondering if this temperature is too low. the car had been warmed up for about 5 minutes, and then this was after about 25 minutes of 60MPH freeway driving, with the hood popped up and was taken will still driving at 60MPH

 

[badjuju]

is there a reason having a low engine temp would suck?

[nbesheer]

Well doesn't it burn more fuel when the engine is cold ?

[badjuju]

a leaner mixture will run hotter.

 

if a motor is just starting, it will run a little more rich to keep it running until it heats up. i would think that so long as your thermistor is functioning, and you really do have a temp above 120*, It's running above the point where this will be happening.

 

Keep in mind, i really don't know the datsun ECUs very well, and everything i just said is likely to be incorrect, but that's what I think.

 

is it possible that it's just colder out than it usually is?

[JessZ]

That temp does not seem too low to me. I ran an l28et without a thermostat for a while and when coasting downhill the temp gauge would barley read above the 120 degree mark. I think that's too low. I could actually feel the engine power change due to the computer telling the injecters to run richer. And when driving around town durning like 60-70 degree weather the gauge would not read as high as the picture you posted. I think your fine.

 

But everything I just said may be wrong too.

[2savage]

An engine that does not reach proper temperature will ultimately have a shorter life due to deposit build-up. That said, your temp guage seems OK. I would say you are in the lower range of normal.

[HowlerMonkey]

I had a 280zx turbo I bought in the winter that had a thermostat stuck open while on the highway.

 

I saw the gauge go down to the bottom and assumed it had an open in the sensor much like some oil pressure sensors do.

 

I would come up a bit but not nearly where it should have been while idling.

 

It was running a bit strange and I got on it pretty hard not knowing the gauge was, indeed correct and found one side of every piston skirt snapped off and in the pan while the other sides were fine on all six after going in to replace rod bearings because there was very slight lower end noise.

 

I guess a 100k mile engine that was probably ice cold has a lot of piston slap.

[johnc]

Temporarily install a calibrated, accurate temp gauge in the engine compartment and see what your actual coolant temps are. 170 to 190 degrees is fine.

[Tony D]

Agreed, the dash gauge is useless. Use a gauge that is known to be accurate.

As long as the engine temperature is above 170F, all the stock ECU functions will be so near the 'normal operating temperature' status it will affect nothing (technically the magic number is 177F.....)

[nbesheer]

Well I'll just drive with the hood closed since It makes the temp go up a bit more

[Gollum]

I've ridden in... lemme think... 7 280ZX cars, and ALL of them read in the middle or down where yours is.

 

My conclusion is what tony D said... the stock guage sucks like a tornado.

 

It's calibration is off at least a good 10% from car to car, but it'll show you a reliable "relative" temperature. If you check the temp with a reliable calibrated meter like johnC said just know that it's fine and watch out for anything higher.