Normal engine temp indication

[edbelton]

What is a normal reading on the temp gauge? When "normal" operating temp is reached, it fluctuates between the right side of the 8 and the middle of the zero (when on stop and go traffic). I have own other watercooled cars and the temp gauge wouldnt fluctuate once the normal operating temp was reached. Any issues here? thanks.

[JFP in PA]

First of all, be aware that the dash gauge is grossly inaccurate as well as non-linear. With an OEM thermostat that begins to open at around 185F, if the dash is showing around “180”, the engine is actually around 210F, or higher………

[edbelton]

thanks JFP, all I was wondering whether it is normal to have the temp gauge swing from between the 8 and the zero (normal temp at normal driving) to passing the half of the zero, at stop and go conditions. Once normal cruise it resumed, it goes back to the original indication, which is between the eight and the zero, straight up. Dont know what temp that is, the gauge is rather fancy than accurate when it comes to readings, all I need to know if that is considered normal. I live in South Florica, and it gets warm, plus traffic here is rather a constant issue. Thanks again.

[m208334]

I have never seen my temperature gauge move abnormally. It is always at about 190 when warm. The fans come on if it gets warmer. See Short Video of Normal Temperature Display when Engine is Warm

[JFP in PA]

It doesn’t move abnormally, it is just ridiculously inaccurate…………..

[edbelton]

Originally Posted by m208334

I have never seen my temperature gauge move abnormally. It is always at about 190 when warm. The fans come on if it gets warmer. See Short Video of Normal Temperature Display when Engine is Warm

Could not download the video, but this ia what I get, will yours go to the traffic marking? thanks.

[m208334]

Yes. Your "Traffic" is when the side fans should be kicking in. However, it takes a fairly hot day and a few traffic lights for the temp to rise from from "No Traffic" to "Traffic".

Note: Agree that it may be inaccurate. I think I misread the original question.

[edbelton]

thanks a lot, it sure takes some time to get there, weather is hot and traffic is heavy down here. Have a good one!

[Gent]

I usually pop the AC on when it starts to push into the zero, that helps keep the temp down in traffic. I was worried that perhaps my fans were malfunctioning, but that is not the case.

Has anyone done a mod to kick the fans in sooner, if only for psychological comfort?

[schnellman]

Okay, so 99% of you already know this, but I can't resist.

Turning on the AC will make your engine run hotter, not cooler.

If you really need to cool the engine a bit, turn on the heater full blast.

[blue2000s]

Originally Posted by edbelton

What is a normal reading on the temp gauge? When "normal" operating temp is reached, it fluctuates between the right side of the 8 and the middle of the zero (when on stop and go traffic). I have own other watercooled cars and the temp gauge wouldnt fluctuate once the normal operating temp was reached. Any issues here? thanks.

That's completely normal and fine for your engine to be in that range.

[edbelton]

if the fan switch doent work, then turning the ac will help, since it will turn the fan on full blast, about the heater, I used to do that in an old vw I had, it makes the water in the heater core circulate, allowing more coolant in the system... good trick, but only as last resource, it gets really hot, top down I guess

[blue2000s]

Originally Posted by schnellman

Okay, so 99% of you already know this, but I can't resist.

Turning on the AC will make your engine run hotter, not cooler.

If you really need to cool the engine a bit, turn on the heater full blast.

Turning on the AC engages a fan that pulls air through the condenser, which also happens to pull more air through the radiator, which lowers the car's coolant temperature.

Turning on the heat operates the fan through the heater coil, which is simply just another radiator that runs through the car's passenger cabin instead of outside the car. It will also lower the engine's operating temperature, but can make things pretty uncomfortable.

[blue2000s]

Originally Posted by edbelton

if the fan switch doent work, then turning the ac will help, since it will turn the fan on full blast, about the heater, I used to do that in an old vw I had, it makes the water in the heater core circulate, allowing more coolant in the system... good trick, but only as last resource, it gets really hot, top down I guess

In our cars, the coolant is always circulating through the heater core.

[jmatta]

Do your car a favor and install the 160 degree thermostat. It may not do much in stand still traffic, but will certainly help all the other times. As JFP stated, the cars run considerably hotter than is indicated on the gauge, which translates to really hot oil temps.

I didn't see if your car was a standard, but if so, also install the "S" engine mounted oil cooler for greater heat dissipation.

[Jake Raby]

we recently gathered some data from a 2000 986S. This engine was running 246F oil temps with the coolant temp at 210, the gauge only said the engine was running a 190F coolant temp.

Adding a low temp thermostat was one of the ways I added the .5 MPH my Wife needed to set a land Speed Record in my 996, actually she broke 4 in one weekend!

[Gent]

Originally Posted by schnellman

Okay, so 99% of you already know this, but I can't resist.

Sometimes obvious ain't right.

[edbelton]

[QUOTE=jmatta]Do your car a favor and install the 160 degree thermostat.QUOTE]

Help me out here, I don't understant the advantage of having a thermostat that opens at 160F. Always thought the thermostat allows the engine to warm up more quickly by restricting some of the coolant from circulating in the system. Once that temp is reached (be it 160 or 185) the thermostat opens and have no control over the final normal operating temp. Thanks.

[extanker]

the fan on/off temps have a large impact on coolant temps. does /can anyone adjust them when they put a lower stat in ?

[tonycarreon]

[QUOTE=edbelton]

Originally Posted by jmatta

Do your car a favor and install the 160 degree thermostat.QUOTE]

Help me out here, I don't understant the advantage of having a thermostat that opens at 160F. Always thought the thermostat allows the engine to warm up more quickly by restricting some of the coolant from circulating in the system. Once that temp is reached (be it 160 or 185) the thermostat opens and have no control over the final normal operating temp. Thanks.

the current understanding is the stock thermostat doesn't start to open until 185, and fully open until 212. the LN thermostat is fully open at 185, allowing the engine to run cooler. also allowing the oil to stay cooler, and the transmission to run cooler..