Rail Temp - Where Is It Coming From?

[Artorias]

So for Gen 1/2 Coyotes, there's no rail temp sensor we all know that. Given that there are slope/offset modifiers based on rail temperature, does anyone know where the inferred data is coming from? Whether that be a single variable or multiple and part of an equation? Making adjustments to this, the car 100% responds to the adjustments so it's definitely an active table.

Trying to figure out where I should be looking to get an idea of what the car assumes the current rail temperature is. I could just physically measure the temperature, but I'd like to know where/how the car is getting inferred rail temp if anyone has a clue. Thank you!

[Witt]

Gen 1/2 use intake air temp as a modifier to those injector tables.

[Artorias]

Gen 1/2 use intake air temp as a modifier to those injector tables.

As a modifier to the tables, or as the source of inferred data for those tables?

If it's the source of inferred data, would you happen to know if it's a 1:1 equation? As in 100F intake temperature the car assumes the fuel rails are 100F

[Witt]

As a modifier to the tables, or as the source of inferred data for those tables?

If it's the source of inferred data, would you happen to know if it's a 1:1 equation? As in 100F intake temperature the car assumes the fuel rails are 100F

Sorry, I meant source. If you're able to log fuel rail temp you'll notice it just locks at 60 something degrees when not equipped with a temp sensor.

[Artorias]

Sorry, I meant source. If you're able to log fuel rail temp you'll notice it just locks at 60 something degrees when not equipped with a temp sensor.

I'd love to hook a temp sensor but I fear the factory OS won't recognize it and make use of it.

Now not saying you're wrong, but going to play devil's advocate here. You would think that assuming fuel rail temp just based off INTAKE temp would be very inaccurate, right? I'd imagine with engine bay heat the fuel rails would always be quite hot and not relative to intake temp at all. I figured maybe some type of equation is used involving ambient temp to assume fuel rail temp

[Artorias]

bump

[Artorias]

bump again, this is exceptionally important information to know if someone has insight. I can confirm air intake temp is not used at all to calculate rail temperature in any sense. Whether intake temps are 40 degrees or heat soaked at 120 degrees, fuel trims follow a pattern and aren't affected.

Who here knows how rail temp is calculated?

[veeefour]

Its based on ECT/EOT/CHT like everything else in those cars.