Tables and parameters we dont see with hp tuners

[02sierraz71]

The more I use this software the more I am beginning to think there are extra parameters and tables we dont have access to. For example I was having problems with getting a consistent afr with pe. I would change the value and the 02's wouldnt relate it but if I made several wot runs then it would start to fall in line and get close to commanded afr. This makes me think there is some sort of learning that goes on with PE that we dont have access to, this also leads me to think that even though the stock 02's are inaccurate at anything but 14.7 the pcm does rely on them when in PE mode.

Is there any chance that some of this stuff is changed with 2.0 or am I completely off?

[jimmyblue]

I know there is way more to be discovered and
untangled within the PCM. Even just the data
section. All kind of stuff "gets done".

I figure in a few years there will be serious OS
rewriters that will also change the face of tuning
(imagine being able to run an OS that wasted no
time on diagnostics or mixture dithering, had a
built in facility for nitrous control and other James
Bond buttons, had higher maximum data limits
for things like airflow and pressure and so on.

Then again, the notion of a GMPP intake, a
Dominator carb and HEI does have a certain
raw appeal.

PE does not learn, but PE will be pushed by bad
learning, or learning of bad conditions. O2s drive
learning. O2s need heat and so on. Follow the
yellow brick road....

I hear in Rel 3.0 we get to command the winged
monkeys.

[02sierraz71]

I know there is way more to be discovered and
untangled within the PCM. Even just the data
section. All kind of stuff "gets done".

I figure in a few years there will be serious OS
rewriters that will also change the face of tuning
(imagine being able to run an OS that wasted no
time on diagnostics or mixture dithering, had a
built in facility for nitrous control and other James
Bond buttons, had higher maximum data limits
for things like airflow and pressure and so on.

Then again, the notion of a GMPP intake, a
Dominator carb and HEI does have a certain
raw appeal.

PE does not learn, but PE will be pushed by bad
learning, or learning of bad conditions. O2s drive
learning. O2s need heat and so on. Follow the
yellow brick road....

I hear in Rel 3.0 we get to command the winged
monkeys.

As long as I get some magic slippers in version 3.0 Ill be happy. What your talking about would be cool.

[Chris@HPTuners]

The more I use this software the more I am beginning to think there are extra parameters and tables we dont have access to. For example I was having problems with getting a consistent afr with pe. I would change the value and the 02's wouldnt relate it but if I made several wot runs then it would start to fall in line and get close to commanded afr. This makes me think there is some sort of learning that goes on with PE that we dont have access to, this also leads me to think that even though the stock 02's are inaccurate at anything but 14.7 the pcm does rely on them when in PE mode.

Is there any chance that some of this stuff is changed with 2.0 or am I completely off?

PE mode doesn't learn, the only thing that will alter your fueling is varying positive fuel trims. If you are using the narrowband O2's as a tuning guide that is your problem right there.

The PCM totally ignores all O2 sensor feedback in PE (or any other openloop) mode. It takes the commanded AFR, airflow and injector flow rate and determines injector pulsewidth without any corrections from the fuel trims unless positive.

[S2002S]

Check out the COT factor....It was controlling my fuel air multiplier.

[02sierraz71]

Check out the COT factor....It was controlling my fuel air multiplier.

Id like to know about the cot setting condition also, I competely removed mine. But I would think maybe if the rear 02's get really hot then it sets the cot not sure.


figured out my PE problem I posted it here

[S2002S]

I'm not sure how the COT condition is triggered. I have longtubes with relocated CATs that are way back, and you would think they would run cooler. I also was told when I had a recent emissions test (OBD-II read) that I had a catalyst secondary air o2 heater readiness monitor problem. The tester said that this was probably because the cats were not up to temperature. Go figure!

[jimmyblue]

COT tries to calculate up the cat temps based on
exhaust airflow, mixture and that kind of thing.
There are SAE science papers written on the
algorithms but they're basically just a headache
waiting to come on. Anyway, the PCM is predicting
an overtemp condition based on assumed stock
cat location and cooling and exhaust heat. With
headers, it knows no different and will still dump
fuel to prevent damage to something that isn't
there, or is way cooler than "believed".

If you want a little bit of protection then set your
max COT to the same value as your max PE. But
with stock cats this likely won't save them from
cooking. It will however help for things like high
RPM, stoich running which -could- hurt the cats,
where PE-level enrichment would cost you only
MPG. Less than total protection, less than total
pig performance, maybe a viable compromise.

But if you burn a cat don't come crying to me. I
took the really safe route and put mine in a nice
dry place.

[02sierraz71]

I just took mine off god I love living in the south

[S2002S]

:'( I'm already crying. Has anyone heard of a fried cat using long-tube headers (with COT disabled)?

[jimmyblue]

Has anyone heard of a fried cat ?

What is this, a Vietnamese restaurant? ;D

I think at really high exhaust flows the headers may
not shed enough heat to save your cats from overtemp
damage. Though I haven't heard much about this there
was a guy on LS1Tech who was doing Salt Flats runs
and cooked his, I believe that car had headers.

[S2002S]

Fried cat is very tasteey.

Thanks again for the advice!