RomRaider

Has anyone dissected the Up pipe EGT sensor usage within the ECU? There is Closed loop Delay based on EGT's, but that's all I could find. Are there any other tables/enrichment based on factory EGT sensor values? I'm working with an 05 LGT 5mt, A2WC510N, all catted up pipe tunes would probably have similar thresholds though.

Reason I ask is, after doing catless up pipe I went with the 2.2-kohm Resistor route (keeps the EGT at 1292*F), my highway mpg's went down. I couldn't blame it on the EGT resistor because I got had to replace the front O2 sensor. Recently set all of the EGT scaling to be at 700*F (about what it was at 70mph on highway), and it looks like my MPG's might have improved a slight bit (1mpg).

I had a quick look for references to EGT but all I really found was related to the OL/CL delay as you known and then some routines for the DTC processing. I didn't find any direct references where it could be used for table lookups. There could be indirect references to the EGT, but these are hard to track down.
I did find one alternate EGT stored value but I can't see what its purpose is. It could be one of the indirect references, but again these are hard to find.

Incidentally I'm using a resistor too. After burning out two EGT sensors I plugged the bung and added the resistor.

Thanks for taking the time to look into it! I think I'm going to have to just do two highway runs to a similar location and see if it makes a difference.