Cold Weather Tuning with HP Tuners?
11-04-2006, 08:03 PM
#1
Cold Weather Tuning with HP Tuners? I live in Michigan and ever since the colder weather moved in 30-40 degree temps my Car seems to have lost power and my Exaust Fumes are much stronger and Fuel Consumption has really gone up.What area's do I need to look at?This is the First Cold weather with my new 408....Thanks! Scott
11-04-2006, 08:50 PM
#2
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Your open loop fuel air table (EQ Ratio vs ECT, MAP)
will be pushing you fat during cold starts. It probably
doesn't need to be as rich as it is.
The O2s are going to have an even tougher than usual
time, when the outside air is sucking even more heat
out of the headers. If it's a closed loop problem then
you might need to look at this some more.
IAT adders for fuel and spark are going to be trying
to participate, and maybe these want to be worked.
First thing to do is get an idea of what the commanded
EQ ratio is, when you see the power loss. Are you
drifting off tune by command, or is it commanding the
same old value but not happy with it now?
Very cold air can also raise your Dynamic Cylinder Air
values and drop your timing (as well as whatever the
IAT, ECT adders tell it, which might compound things
or compensate, depending).
will be pushing you fat during cold starts. It probably
doesn't need to be as rich as it is.
The O2s are going to have an even tougher than usual
time, when the outside air is sucking even more heat
out of the headers. If it's a closed loop problem then
you might need to look at this some more.
IAT adders for fuel and spark are going to be trying
to participate, and maybe these want to be worked.
First thing to do is get an idea of what the commanded
EQ ratio is, when you see the power loss. Are you
drifting off tune by command, or is it commanding the
same old value but not happy with it now?
Very cold air can also raise your Dynamic Cylinder Air
values and drop your timing (as well as whatever the
IAT, ECT adders tell it, which might compound things
or compensate, depending).
11-05-2006, 09:50 PM
#4
Originally Posted by Pro Mouse
As far as I can Tell my Tuner has my tune not ever seeing Closed loop.My Closed loop enable Coolant temp vs. IAT set to all values of 302.So without WB I shouldnt be Touching Open Loop F/A vs. ECT vs. MAP ,correct?
Thanks!
Thanks!
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11-05-2006, 10:49 PM
#8
Thats strange,How could it be 302 than?It beats the Hell out of me.My Guess is he has it staying in open loop all the time.So I really cant tune it without WB.The car loses seems to lose SOTP performance in colder weather.Back when these numbers were 92 stock values the car Ran alot better in colder temps...
11-06-2006, 06:59 AM
#10
Originally Posted by Pro Mouse
Thats strange,How could it be 302 than?It beats the Hell out of me.My Guess is he has it staying in open loop all the time.So I really cant tune it without WB.The car loses seems to lose SOTP performance in colder weather.Back when these numbers were 92 stock values the car Ran alot better in colder temps...
11-06-2006, 09:30 AM
#12
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Originally Posted by foff667
odd...no I mean theres a pcm limit that shouldnt even be able to go over 284F I have no clue how its reading 302 in that table.
11-06-2006, 09:56 AM
#13
Originally Posted by Somebody09
If it can go up to 284 then it should have no problem going to 302. If you think about the bits required for memory, not even 284 as a max doesn't make sense (minimum of 9 bits required for both numbers)... not in binary, quat, oct, or hex. If 284 is a max then I'd love to know what the hell GM is doing, or if they're assuming coolant temps can't get below 28°F
11-06-2006, 12:00 PM
#14
Originally Posted by foff667
yeah i dunno...thats what it lists the min/max at.
I've downloaded tunes previously tuned by ls1 edit, tunercat ect that had out of range numbers. However the tune still seemed to work. Either those programs did not have a max/min or hpt is converting the numbers incorrectly.
11-06-2006, 09:16 PM
#15
Mine is set to 284 degree's ,I am running an older version of HPT.The catagory I speak of is Closed Loop enable Coolant Temp vs. IAT...The range goes from -40 F to 284 F all these values are 302,There is a Total of 19 numbers and all are 302.The ect used to be set at 92 F....
11-07-2006, 11:23 PM
#16
Originally Posted by SmokingWS6
I've downloaded tunes previously tuned by ls1 edit, tunercat ect that had out of range numbers. However the tune still seemed to work. Either those programs did not have a max/min or hpt is converting the numbers incorrectly.
I have seen this as well on 2 previously tuned with LS1edit.
11-08-2006, 10:28 PM
#17
Originally Posted by SmokingWS6
I've downloaded tunes previously tuned by ls1 edit, tunercat ect that had out of range numbers. However the tune still seemed to work. Either those programs did not have a max/min or hpt is converting the numbers incorrectly.
11-09-2006, 02:19 AM
#18
Originally Posted by Pro Mouse
Mine seems to work ok,Except in the Colder weather seems to be pig fat
When the engine is cold or all the time? If your in open loop you need to check the commanded afr vs temp in the OLFA table. Its quite possible your dumping fuel in excess if its still retaining stock values.
11-09-2006, 09:42 AM
#19
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HPTuners clip limits are put down for sanity bounding
but I have run into other tunes (e.g. Predator) that
put higher, nonsensical even, values in some things.
The limits imposed are outside the range of sensible
settings generally, but don't necessarily correspond
to the PCM maximum representable value (like the
thing wouldn't be blowing orange flavored chunks
all over the engine bay at 284F or 302F anyway).
Not necessarily true that it's one bit per degree
either, some params are represented with less
resolution, might be 8 bits for -40 to {whatever}
and PCM bits being translated to closest human units
behind the scenes. When you push a new value and
it "snaps to grid" (something close, but different and
even) this is what's going on.
Have you done the logging yet, to see where the
enrichment is coming from?
but I have run into other tunes (e.g. Predator) that
put higher, nonsensical even, values in some things.
The limits imposed are outside the range of sensible
settings generally, but don't necessarily correspond
to the PCM maximum representable value (like the
thing wouldn't be blowing orange flavored chunks
all over the engine bay at 284F or 302F anyway).
Not necessarily true that it's one bit per degree
either, some params are represented with less
resolution, might be 8 bits for -40 to {whatever}
and PCM bits being translated to closest human units
behind the scenes. When you push a new value and
it "snaps to grid" (something close, but different and
even) this is what's going on.
Have you done the logging yet, to see where the
enrichment is coming from?
