COT temperature thresholds

[my_bd]

anyone know anything about how the LSJ P12 pcm manages the cot protection feature?
what kind of funky voodoo magic crystal ball gm logic is going on inside that thing?

seems the cat temp is calculated from a bunch of other parameters, since there is no temp.sensor on or near the cat.
I found this old thread with an aged article attached about how cat temps are derived via all kinds of crazy math calcs using a variety of other available parameters such as mass air flow and afr, etc.
http://www.hptuners.com/forum/showpo...56&postcount=5

in the stock tune we have 4 adjustable temperature thresholds, a base enrichment rate, and a max enrichment rate.
see attached pic for reference.

I'm wondering how the thresholds and enrichment rates are applied since the thresholds are not increasing from lowest value to highest value, doesn't make any obvious sense.

Would the pre-programmed cot values only be valid and useful on a completely stock vehicle with its original cat installed?
If mods or a different cat are installed would the cot parameters be useful still?

(on a side note I also don't understand the assigned HPT label reference to altitude - "cot thresholds vs Altitude range"???)

[redhotjamedjimi]

just give chevy and the us gov't the middle finger and turn cot off. my guess is considering the 05-07 cobalts arent emmisions friendly your whole confusion is the reason why its not the best on emmisions. how turbocharging the lsj is what baffles me. dont turbos run alot richer?

[MMGT1]

COT, "In my opinion", is OUT! You are scaning and tuning all the time. If there is a problem, you'll know. Mine is set to max enable and AFR is equal to the PE AFR...

[my_bd]

but my question is how do you monitor the temperature of the cat if it is not a stock cat, nor stock exhaust, not to mention the myriad of other mods?

The reason I ask is because from what I have seen and read so far, it sounds like the pcm is specifically programmed to figure out the probable temperature of the stock cat with stock exhaust running with a stock tune, etc.
(I don't truly understand why it is calculated rather than measured)

Sure we can monitor afr, egt's, air flow, and any other sensors or pids avail in HPT, but there is no way for us to really know how hot an aftermarket cat is
....is there?