I got a ScanGauge II yesterday and set it up to monitor oil, coolant, and trans fluid temps. I discovered I must need a new thermostat because my ECT (or *FWT as it is displayed) never gets over about 185 running empty in 65 F air temps.

Anyway, my question is in regard to the EOT readings I'm getting. This morning before the sun came up, I checked the three temps before running the truck and discovered that the EOT was reading about 4 degrees higher than TFT and ECT. The latter two were both the same (60 F). The truck had been sitting for more than 12 hours. I am using the following Xgauge settings for EOT:

TXD: 07E0221310
RXF: 046205130610
RXD: 3010
MTH: 000901F4FFD8
NAM: EOT

I first tried programming EOT using the settings in the Xgauge PDF on the ScanGauge site, but the thing was reading WAY too high. Then I found where guys with 2004 trucks were using the above settings with success (mine is an April '04 build).

Do I need to tweak the MTH setting to make the cold EOT read the same as the ECT and TFT? If so, how do I do this? I looked at the Xgauge Coding guide and got a headache. Any help appreciated. Thanks!

 

I also have lower than expected fwt and have version 3.15 of the xgauges. Do you have 3.17?

 

Amgpro2, yes I have firmware 3.17mB. I just bought my ScanGauge on Amazon.com, so I assume it's the latest version(?).

At first I wondered if the ECT was reading low, but after I saw it was exactly the same as the TFT temperature this morning, I assumed it must be reading right and my T-stat must need replacing. The EOT, however, was reading 4 degrees higher than both ECT and TFT. This afternoon, however, when the air temps rose to about 75 F and the sun had been out for a while, the EOT was only 2 degrees higher than ECT (engine still cold from not having been started yet).

I guess the variance could be the two sensors just fluctuating within ± a couple degrees of their designed specs...I dunno.

 

I have the Insight and have noticed a 2 to 4 degree difference between ECT/EOT prior to starting the engine for the first time of the day just like you. It's been that way since the first time I installed the monitor. I've just chaulked it up to varience between the sensors.

 

Thanks Frank. I suspect you are right about the sensor variances. I guess I'll just put in a new T-stat and then watch to see how things look over time.

And thanks to all you ScanGauge users who posted their experiences on the site. I learned a lot from reading them!