Hi,

My 2002 V8 is being used by my eldest son now he can drive. He's keen but very inexperienced and I want to put in an external temp gauge. Doing reserach I see a lot of people recommending Ultragauge, and I like the fact it's a dead easy plug in. My concern, however, is that it uses the same data that feeds the existing temp gauge, and therefore wonder how accurate the gauge really is. I wanted to ask if anyone has any info on the accuracy of the Ultragauge, for example having compared its readout with information taken from a physical sensor inserted into the cooling system, or a physical in-line gauge? Or do folks generally trust Ultragauge? Thanks.

 

It sounds like you probably get this, but here's a little clarification for anyone else who reads it.

There is NO accuracy component to the UG. It is only displaying what data are sent to it by the ECU. Further, there is no accuracy problem with the temp gauge. The problem is with the way the temp gauge was designed to work. If there is a failure, or degradation of performance of the temp sensor, then there will be accuracy problems. But, you will have performance problems along with that since that is what the ECU uses to run the engine. So, the UG presents good data, good in that it accurately represents what the ECU believes is going on.

Absent some failure in the system, the UG gives great info. Get one, use it. Don't forget to get the Golden Rovers mount too.

 

The problem with the gauge in the instrument cluster isn't the information being provided to the ECU by the sensor, it's how the information is displayed on the dash. The ECU feeds the dash gauge a predefined signal to get the needle to move. The issue is that the signal isn't linear to the temp. As my truck comes up to temp the ECU signal causes the needle to start to rise. When I get to 165° on the Ultragauge, the needle finds its spot right in the middle of the scale. As I get on up to 190° on the Ultragauge, the needle still sits unwavering right in the middle because the ECU hasn't increased the signal despite the sensor reporting significantly higher temps. I've never had the truck get over 210° however even then the needle sat right in the middle. A 45° swing in temp with no change to the dash gauge is at best ridiculous, but practically criminal in my opinion. I don't know when the ECU increases the signal in order to raise the needle but by most accounts unless you witness it just as it starts to move, by the time it's moving the engine temp is so high you're well on your way to catastrophic failure. The buffered signal is what makes the dash gauge so unreliable as a warning system.

The Ultragauge can be programmed to sound an audible alert at a preset temp. This means you don't even have to be looking at it to be alerted to a possible overtemp situation. I would highly recommend buying one. They used to sell an Ultrablue dongle that used a bluetooth connection to a phone or tablet but for some reason they've discontinued them.

As pointed out, it the temp sensor itself goes wonky then the reported temps will not be valid, but most likely you'll get a code (or many) before the potential for an overheat to occur.

 

It is accurate if the temp sensor on the engine is accurate.

Data coming from the same place. The problem is not with your temp sensor, it’s with the dummy gauge that displays dumbed down ranges, as I’m sure you know.

I set my UG temp alarm for 210.

 

Our stock temp gauge is no better than an idiot light.

 

Thanks all - useful to know that you trust the UG. I put my Nanocom on today as I was running errands around - some highway, some stop and go. It's quite cold outside (north of Toronto) at about -5C. The engine warmed up very quickly at idle and sat between 89-92C for the 3 hours I was driving according to the Nanocom.

@H20nSnow Thanks so much for the pointer on the Golden Rover mount. Had no idea it existed. Will order one when the gague arrives (assuming the link on AliExpress isn't fake...!)

 

goldenrovers.com

 

Golden rover mount is the best ! One note, I went with the black one for my grey interior, it looked better than the grey one.