Porsche 944 aftermarket water temperature gauge

From my experience, old Porsches tend to have wiring corrosion issues. And amongst other things, corroded wires can affect the accuracy of your gauges. This is a common occurrence with the water temperature gauge in early-model Porsche 944s. And as a result, the temp gauge in your 944 could very well be reading inaccurately. Here’s a couple common symptoms that your gauge may be straying from accuracy.

Turning on the headlights will notch-up the temperature gauge.

The temperature gauge may ‘flick around’ as if it was binding.

General inconstancy during what should be consistent regular driving.

If the water temp gauge in your 944 is on the fritz…

It tends to read a bit hotter than what’s accurate. And while that may be good from an engine-protection standpoint, it can create a stressful driving experience. Before adding the new water temp gauge on my 944, I had gone through some general cooling system trouble-shooting. Initially, I flushed the cooling system a couple times. Then I installed a lower temperature fan switch & upgraded to late-model 944 radiator fans (they move more air). Additionally, I cleaned the connection to the temperature sender, and pulled the instrument panel to clean all the connections & grounds at the gauges themselves. This is all good stuff. But the factory gauge still wasn’t giving me a sense of trust. So finally, I ordered a new water temperature gauge from Prosport Gauges.

Glenn Cohen from Prosport Gauges…

Is a longtime friend of S3 Magazine. I’ve known him for over a decade, and Prosport puts their heart into making great products. The Prosport temp gauges all come with a new, much more precise & accurate temperature sender. And their gauges have automatic alert, which will warn you if you go over your set max temperature. Couple other things: the 52mm gauges come with a pod for mounting (should you need one). And you can piggyback multiple gauges off each other. So if you add more gauges later, you can just jump-power from one gauge to the next.

Prosport makes different styles gauges…

I went with the Premium Series… specifically the sub-model with the White Pointer. Reason being: The White Pointer gauges come with a clear lens that compliments the 944’s older 80’s-era interior nicely.

Prosport also offers a radiator hose adapter…

The radiator hose adapter makes installation of the new (included) temperature sender quick & easy. Go with the 38mm option for the Porsche 944. I mounted the adapter as discretely as possible under the 944’s mass-air-sensor box. From there I was also able to run the wire from the temp sender inconspicuously, and enter the firewall through the factory harness grommet.

Mounting the gauge…

The 52mm (2-1/16″) Prosport gauge is conveniently the same size as the 944’s clock. And I’m pretty sure that clock didn’t even work anymore anyway… so I pulled it out & kicked it into the woods so archeologists would have something to marvel about in a thousand years. Just kidding I didn’t do that. But as an added convenience, with the clock out of the car (& responsibly stored), I was able to easily pull 12v power, ground, and illumination right from the wires that originally went into the back of the clock. And the final ignition power was easily pulled from the AC dial right next door.

The verdict…

So far (knock on wood), thanks to the new Prosport gauge, I can see that the 944’s water temps are actually satisfactorily stable. And that’s given me a LOT more confidence in the car. It’s taken the anxiety out of the 944’s driving experience, and filled that void with a LOT more enjoyment.

The running temp of a Porsche 944 depends on many different factors, but if you’re generally just curious about some numbers, my 944 seems to be settling-in at around 190-205°F, and that’s in hot & humid Georgia summer heat. Catching a red-light in the middle of spirited driving, the car may experience a temporary surge of heat… at which point the gauge alerts me as it hits the 210° mark (you can set the alert to whatever temp you desire). But so far – the 944 has been able to pull the temps back down on its own. More miles will yield more data. But the point is: With the Prosport water temp gauge, I now have the instrument to accurately see what’s happening.