OEM Engine Coolant Temperature vs Performance Monitors

[220629]

The OEM engine coolant temperature is obtained from the same sensor whether the display is the OEM dash gauge, or a performance monitor Eg. - Scangauge II, Ultra gauge, Nautabox (Nautybox?). The sensor is the same. There may be some error in scaling of the OEM analog gauge vs a digital display. For those who have aftermarket performance monitors, how do the temperatures compare OEM vs aftermarket.

I just use the OEM gauge. Digital displays always appear more precise, but depending upon the sensor signal conditioning they can have small errors over a range.

vic

 

[Kajtek1]

When I don't have temp gauge on my Sprinter, living in hot climates I have to observe engine temperatures very closely.
The 1998 E300DT and 2008 E320 Bluetec did have digital sensor displays on its climatronic.
The steam gauge on dashboard and digital on climatronic were showing different temperatures.
I could never confirm if they have different sensors, or the cluster gauge has dummy software who was keeping the reading to please the eye.
Bottom line, I always drive with ScanGauge showing coolant temp, DPF load and couple of other readings that I change from time to time.

 

[trc.rhubarb]

I've found that my gauge, while fairly accurate, seems dampened compared to digital readings that I've seen on my AP200 and my MBII. It doesn't react to quick fluctuations, which is likely by design to prevent panicked responses.

 

[Kajtek1]

I've found that my gauge, while fairly accurate, seems dampened compared to digital readings that I've seen on my AP200 and my MBII. It doesn't react to quick fluctuations, which is likely by design to prevent panicked responses.

That's what called "dummy" feature. Common for last 20 years software programs who will not alert the driver unless the situation become critical.
That is why they canceled oil pressure gauges over 20 years ago.

 

[trc.rhubarb]

It's not acting like a dummy gauge... it moves progressively just does it slower... just a modern fuel guage, vs reacting to every small deviation.
On a cool day, on flat roads, i bisect the 8 nearly perfectly... if it's in the 90s, i'm a little higher on the 8... if i hit a grade under high load and hot out, it goes up progressively closer to the 215 line and stops there, then drops progressively as the load lessens.

I tend not to slow down for grades as the van doesn't "ask" me to but I do watch temps to be sure.

A dummy gauge is generally like what's in my old Honda... it's either cold, just right or hot (truly had just 3 positions). Nothing really in-between. This is, at least in my 2003, an actual gauge with accurate readings but seems to use an average over say 10 seconds or so vs instant read/change.

 

[Kajtek1]

I'd say that Japanese dummy and German dummy are different dummies
Than I used to drive Ford Truck with "famous" 6l Powerstroke.
The engine was famous for clogging EGR and oil coolers, while having dummy temp gauge.
By the time the gauge start moving to the red zone and I was able to pull over, there was not much left from 4 gallons of coolant.

 

[Zundfolge]

My SG2 pretty closely emulates the stock needle. I've always just watched needles move my whole life until the SG2 entered my life, and have never had an issue, but I gotta say! Being able to see the actual number is really nice at a glance sometimes!

I know you're anti-digital readouts Vic, but there is something to it

 

[220629]

...
A dummy gauge is generally like what's in my old Honda...
it's either cold, just right or hot (truly had just 3 positions). Nothing really in-between. This is, at least in my 2003, an actual gauge with accurate readings but seems to use an average over say 10 seconds or so vs instant read/change.

I had that impression with the temperature gauge on all of the B series Dodge vans that I owned. As time passed and the aluminum heads got thinner and thinner, by the time the gauge told you the engine was hot the heads had likely cracked between the valves.

My SG2 pretty closely emulates the stock needle. I've always just watched needles move my whole life until the SG2 entered my life, and have never had an issue, but I gotta say! Being able to see the actual number is really nice at a glance sometimes!
...

Good to hear.

I know you're anti-digital readouts Vic, but there is something to it

I'm not anti-digital. I'm just not a gadget guy. Different displays have their place.

I like the Turbo Boost direct read pressure gauge in the 2004. I had the stuff cheap to put it together. An advantage is that it does give a separate reading that could help to verify whether the boost sensor itself was a problem. That's a minor advantage though. It makes sense for most owners to just buy some sort of aftermarket performance monitor to get turbo boost, system voltage, etc. I wouldn't invest in a performance monitor that didn't include TCM temperature. If you're spending the money, spend enough to get that. (I have the parts for the 2006 boost gauge, but haven't been motivated. You can drive a Sprinter just fine using just the stock instrumentation.)

I prefer using a digital readout compass when sailboat racing. As you say, the numbers seems to stick in human memory better than spoken readings from a card compass. That said, any distance racing I've done I always pack my old Boy Scout compass as a backup.

vic

 

[lindenengineering]

Some figures to digest from previous posts for T1N's :-

The ability of the radiator is to reject heat at full power heat input is different than low power light cruising at 65 mph. The radiator must be able to reject heat across the power range attaining a constant stabilized top pipe temp under full power delivery to avoid thermal stress
The viscous coupling will couple at 101 to 107 c as I mentioned (107 is 224f ) most new ones couple at 101 c.
Bulk oil temperatures on most if not all engines is always higher than the cooling system.
The benchmark new is always 12 to 15 Celsius above coolant in almost all designs
Dennis

 

[tom2turbo]

The viscous coupling will couple at 101 to 107 c as I mentioned (107 is 224f ) most new ones couple at 101 c.
Bulk oil temperatures on most if not all engines is always higher than the cooling system.
The benchmark new is always 12 to 15 Celsius above coolant in almost all designs

Good to have data points. Thanks

 

[tbuyan]

The benchmark new is always 12 to 15 Celsius above coolant in almost all designs
Dennis

That's 21.6º to 27º F in the "old" system here in the new world.