Question about PRNDL
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Teching In
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Question about PRNDL I just got a 4L80 added behind my 6 liter in my 1966 LandCrusier. It has no PRNDL switch, and I was fiddling with the PRNDL setting in the editor and in the scanner to get a feel for which idle table is used (drive or park/neutral) when there is so switch installed.
What I discovered confused the hell out of me. With PRNDL set to 'none' in the editor, the PRNDL status in the scanner works perfectly - Park, Reverse, Park, Drive, etc. However, if you set PRNDL in the editor to 'PRNDL', then the PRNDL status in the scanner sits at D4. Why?
Also, when PRNDL is set to 'none'. Which idle table is used - drive or park/neutral?
Peter
What I discovered confused the hell out of me. With PRNDL set to 'none' in the editor, the PRNDL status in the scanner works perfectly - Park, Reverse, Park, Drive, etc. However, if you set PRNDL in the editor to 'PRNDL', then the PRNDL status in the scanner sits at D4. Why?
Also, when PRNDL is set to 'none'. Which idle table is used - drive or park/neutral?
Peter
it uses the in gear idle table but more importantly it uses the base running airflow table for drive as well
designating no switch just eliminates the manual kickdown tables
if you still have an 80e or 60e selected in transmission, it'll run off the pressure switches to determine gear if no prndl is present
designating no switch just eliminates the manual kickdown tables
if you still have an 80e or 60e selected in transmission, it'll run off the pressure switches to determine gear if no prndl is present
Thread Starter
Teching In
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Thanks Truckdoug
So, set to 'none', it uses the in gear and base running airflow tables.
But the PCM still knows what gear it's in using the pressure switches.
I have 4L80E selected.
I'm not getting what Manual Kickdown means - I can't find it in my HPTuners
I've been running into that a lot lately where people talk about a setting, show a screen shot, and I go to HPTuners and mine looks totally different.
It only adds to the massive level of confusion.
Do I care I care if I don't have manual kickdown?
So, set to 'none', it uses the in gear and base running airflow tables.
But the PCM still knows what gear it's in using the pressure switches.
I have 4L80E selected.
I'm not getting what Manual Kickdown means - I can't find it in my HPTuners
I've been running into that a lot lately where people talk about a setting, show a screen shot, and I go to HPTuners and mine looks totally different.
It only adds to the massive level of confusion.
Do I care I care if I don't have manual kickdown?
manual kickdown probably not the right name for it. it is like a different set of upshift and downshift speeds based on what gear you have selected on the prndl
there's a set of tables under trans > auto shift speed > part throttle shift
from what I can tell they are directly controlled by the prndl switch only.
I try and always unify these tables unless a customer asks me to keep the tow-haul mode or performance switch. It really makes life easier when the trans controller isn't trying to get smart on ya!
there are also a set of tables right next to it that say "full throttle shift speed" and "full throttle shift rpm"
it's important to not only unify those tables but use that same data from each one. it uses some sort of long polynomial to calculate the actual shift speed from all the numbers there.
for this I use Bluecat's transmission tuning tool. It's super easy, just punch in your data, hit export and the copy paste the outputs into the shift speeds tables
https://forum.hptuners.com/showthrea...Table-Software
and yes it gets confusing, the deal is that each OS stores the information in slightly different places, so each file definition looks a little different. a lot of stuff is very similar though, or at least has the same name ( in the p01 and p59 computers at least)
there's a set of tables under trans > auto shift speed > part throttle shift
from what I can tell they are directly controlled by the prndl switch only.
I try and always unify these tables unless a customer asks me to keep the tow-haul mode or performance switch. It really makes life easier when the trans controller isn't trying to get smart on ya!
there are also a set of tables right next to it that say "full throttle shift speed" and "full throttle shift rpm"
it's important to not only unify those tables but use that same data from each one. it uses some sort of long polynomial to calculate the actual shift speed from all the numbers there.
for this I use Bluecat's transmission tuning tool. It's super easy, just punch in your data, hit export and the copy paste the outputs into the shift speeds tables
https://forum.hptuners.com/showthrea...Table-Software
and yes it gets confusing, the deal is that each OS stores the information in slightly different places, so each file definition looks a little different. a lot of stuff is very similar though, or at least has the same name ( in the p01 and p59 computers at least)
Thread Starter
Teching In
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Ah, that makes sense. Mine has all this stuff under Part Throttle Shift about Upshift D2 2nd, Upshift D2 3rd that I assume is the stuff that only works if PRNDL is set to PRNDL and there's actually a switch there. So, on my 4L80, shifting into D3, 2 or 1 will cause the tranny to do the right thing, but the shift points won's adjust using those part throttle tables. There are also tables there for normal, performance, cruise, etc - which I assume only come into play when the appropriate 'sport' switch is present.
I'm never going to run this rig WOT, unless I'm getting on the freeway in front of a semi. But I'll take your advice when I get to that point and unify the tables.
Right now, I'm struggling with getting idle right. So, I'm going to set the PRNDL to none and unify the in gear and park/neutral tables in idle and work on the VE table down low.
Now, I've got a TPS of some very small value. Apparently my TPS, usually at .66 or .67 volts, occasionally stops to .65 which then causes a nonzero TPS value when it comes back to .66/.67. Not sure what to do about that.
I'm never going to run this rig WOT, unless I'm getting on the freeway in front of a semi. But I'll take your advice when I get to that point and unify the tables.
Right now, I'm struggling with getting idle right. So, I'm going to set the PRNDL to none and unify the in gear and park/neutral tables in idle and work on the VE table down low.
Now, I've got a TPS of some very small value. Apparently my TPS, usually at .66 or .67 volts, occasionally stops to .65 which then causes a nonzero TPS value when it comes back to .66/.67. Not sure what to do about that.
one last note on the 80e, just make sure it's in D3 if you do have to beat on it. they die young if you do a lot of whooping on 'em in D4
so am I reading that right the TPS has a dead spot in it? if so shitcan it. TPS is involved in just about every calculation the computer makes from fuel to spark to shifting, etc
lemme know when you get a good one I'll make a video or something on how to dial in your base running airflow, adjust the throttle blade and reset the IAC motor so it idles nice. you got a cam in it or stock?
so am I reading that right the TPS has a dead spot in it? if so shitcan it. TPS is involved in just about every calculation the computer makes from fuel to spark to shifting, etc
lemme know when you get a good one I'll make a video or something on how to dial in your base running airflow, adjust the throttle blade and reset the IAC motor so it idles nice. you got a cam in it or stock?
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Thread Starter
Teching In
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I got a bigger cam. Not huge, but far from stock. I don't know what it is, it came with the engine.
Not sure what the deal is with the TPS. I can see the voltage sitting at .67 and the TPS moving between 0 and. 0.4%.
I love to get your input on base idle air flow, because it's screwed up right now.
Based on what I've reading, I'm correcting my MAF and then will go to work on my VE table to get it close.
I appreciate the help.
I'm going to post up my MAF info to get some help with that.
Not sure what the deal is with the TPS. I can see the voltage sitting at .67 and the TPS moving between 0 and. 0.4%.
I love to get your input on base idle air flow, because it's screwed up right now.
Based on what I've reading, I'm correcting my MAF and then will go to work on my VE table to get it close.
I appreciate the help.
I'm going to post up my MAF info to get some help with that.
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Verdad Gallardo ok thats not a big deal. you may need to reset the TPS and IAC. here's a good, brief write up on it
https://sites.google.com/site/sloppy...ls/iac-relearn
usually I bump base running airflow in both park/neutral and in gear by about 5% per 10 degrees of camshaft duration over stock.
https://sites.google.com/site/sloppy...ls/iac-relearn
usually I bump base running airflow in both park/neutral and in gear by about 5% per 10 degrees of camshaft duration over stock.