Thread: Low coolant/high temp alarm sensor

Originally Posted by BathurstTom

Hi Ace, I'm in Kelso. I took my 97 300TDI auto out on a hot day about a month ago to test it. I went out to Yetholme at about 1.30 with AC on and I was pushing about as hard as I could (you know the hills out that way). It was 36 C at the time and the temp on the digital guage got up to 103.


Cheers,
Tom.

Mine goes higher than that without AC, I've had mine to 112 heading back towards Bathurst towing my camper with the climb from the end of the dual lanes out of Lithgow and up Mt Lambie. The cowl has helped a bit, I'm hoping the new viscous fan fixes it.

Once I have the fan sorted I'll go for a test and see how that goes. The cooling system is good aside from the viscous clutch on the fan so if that doesn't sort it I don't know where to go from there. I think the location I have my sensor on isn't the best, it's on the block where a bracket bolts on on the injector side away from the manifold. I'll sort the fan tomorrow and move the sensor and see how I go.

Matt

Originally Posted by Ace

And the aircon doesn't drive the temp up much higher?

Yes it can do on really hot days certainly moreso (and quicker) than when AC is not on.

When you're going up hill are you losing power and having to floor it thereby going up gears? Is it auto or manual?

My comment from experience... I have both the head temp sensor and a coolant temp sensor. The head temp sensor is a good gauge at temps, BUT its is not the same as coolant temp. I have seen fluctuations in head temp, but coolant temp is more controlled (obvious).

Having both, I would say the coolant temp is much more reliable indicator of engine temp, and if you had a choice, get that over the head temp. I got vids on how I did the coolant temp installed, basically using the original coolant temp sensor location thus disabling the dash gauge.

Originally Posted by stooge

My comment from experience... I have both the head temp sensor and a coolant temp sensor. The head temp sensor is a good gauge at temps, BUT its is not the same as coolant temp. I have seen fluctuations in head temp, but coolant temp is more controlled (obvious).

Having both, I would say the coolant temp is much more reliable indicator of engine temp, and if you had a choice, get that over the head temp. I got vids on how I did the coolant temp installed, basically using the original coolant temp sensor location thus disabling the dash gauge.

I would disagree on this. The temp of your steel(alloy head) is what is important. All new cars run their temp gauges off engine steel, not coolant.

As for temps. I purchased a brand new head from turners in the UK. At the same time I fitted one of these.

ENGINE WATCHDOG TM2, Engine Temperature Sensor and Low Coolant Alarm

I bolted the sensor to the head as this in my opinion is the best place to monitor the engine temp. I then rang Turners to ask for advice on safe max temp and they told me 110 degrees was ok.