> PE, no change - Any ideas?
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From: St. Paul
> PE, no change - Any ideas?
Working with a 730 pcm, S_AUJPV3 and have made some significant changes to PE at higher RPM in an effort to richen things up when it hits PE. I can see it go into PE just fine and it's mid 12's for awhile and then around 3500 it starts to go lean. Even after significant changes I'm seeing no change. Any ideas on what I could be missing? I'm using the "Enrich Power Change to AFR vs. RPM" in TP with the Super_8Dm2.xdf. Logging AFR from an LM-1 so I'm getting a pretty accurate look at it.
Having some other issues as well but will start with this one.
Thanks!
Todd
Having some other issues as well but will start with this one.
Thanks!
Todd
Joined: Mar 2000
Posts: 1,692
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From: Corona
Car: 92 Form, 91 Z28, 89 GTA, 86 Z28
Engine: BP383 vortech, BP383, 5.7 TPI, LG4
Transmission: 4L60e, 700R4, 700R4..
Axle/Gears: 3.27, 2.73
Re: > PE, no change - Any ideas?
Do you have a very powerful engine and small injectors? Or maybe very low fuel pressure at high RPMs?
That's what'd I'd check first...
That's what'd I'd check first...
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From: St. Paul
Re: > PE, no change - Any ideas?
Pretty sure the injectors are sized okay but the fuel pressure is certainly worth checking. I'll throw the gauge on there and see what it does at the higher RPMs. Thanks
Todd
Todd
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From: GA
Car: '90 C1500
Engine: SBC MPFI
Transmission: 4L80e
Axle/Gears: 4.30
Re: > PE, no change - Any ideas?
What temp is your PE constant set too.....it will only enable at a certain temperature in the Constants settings..Enrich Power AFR enable Min Temp. If its set to something higher than operating temp of your engine then you need to adjust VE table instead. Oh...that's in TunerPro RT.
Fuel pressure is another idea worth checking out.
Fuel pressure is another idea worth checking out.
Last edited by YenkoST; Sep 30, 2007 at 09:19 AM.
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Re: > PE, no change - Any ideas?
Could just be that the upper VE cellshave not been tuned properly, I'm struggling with the same issue where PE fuel is off the chart so to speak but I'm running lean at higher RPMs.
Raise the cells that have a hard time getting to (just a bit) and try again to see the results.
Raise the cells that have a hard time getting to (just a bit) and try again to see the results.
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From: GA
Car: '90 C1500
Engine: SBC MPFI
Transmission: 4L80e
Axle/Gears: 4.30
Re: > PE, no change - Any ideas?
Could just be that the upper VE cellshave not been tuned properly, I'm struggling with the same issue where PE fuel is off the chart so to speak but I'm running lean at higher RPMs.
Raise the cells that have a hard time getting to (just a bit) and try again to see the results.
Raise the cells that have a hard time getting to (just a bit) and try again to see the results.
Joined: Apr 2004
Posts: 3,180
Likes: 3
From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Re: > PE, no change - Any ideas?
The temperature setting selects which of the two tables are used for the PE engagement. It will not actually turn PE on/off, just the points where it comes in at are changed in the other table.
There is a low temp table and a high temp table that are shown below.
The variable at $8602 determines which one is used.
As I understand it, this allows PE to be engaged sooner with high temps to possibly use additional fuel to cool the chambers.
There is a low temp table and a high temp table that are shown below.
The variable at $8602 determines which one is used.
Code:
;----------------------------------------------------------------
; PWR ENRICH TPS THRESHOLD vs RPM
; FOR NORMAL COOLANT
; *** WOT ***
;
; TBL = TPS% * 2.56
;----------------------------------------------------------------
; VAL %TPS RPM
;--------------------------------------
L8603: .byte 0x80 ;=128, 50 400
.byte 0x80 ;=128, 50 1200
.byte 0x80 ;=128, 50 2000
.byte 0x9A ;=154, 60 3200
.byte 0xB4 ;=180, 70 4800
;----------------------------------------------------------------
;----------------------------------------------------------------
; PWR ENRICH TPS THRESHOLD vs RPM. FOR HIGH COOLANT
; *** WOT ***
;
; TBL = TPS% * 2.56
;----------------------------------------------------------------
; VAL %TPS RPM
;--------------------------------------
L8608: .byte 0x80 ;=128, 50.0 400
.byte 0x80 ;=128, 50.0 1200
.byte 0x26 ;= 38, 14.8 2000
.byte 0x26 ;= 38, 14.8 3200
.byte 0x26 ;= 38, 14.8 4800
;---------------------------------------------------------------- Last edited by JP86SS; Oct 1, 2007 at 11:49 AM.
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From: GA
Car: '90 C1500
Engine: SBC MPFI
Transmission: 4L80e
Axle/Gears: 4.30
Re: > PE, no change - Any ideas?
The temperature setting selects which of the two tables are used for the PE engagement. It will not actually turn PE on/off, just the points where it comes in at are changed in the other table.
There is a low temp table and a high temp table that are shown below.
The variable at $8602 determines which one is used.
As I understand it, this allows PE to be engaged sooner with high temps to possibly use additional fuel to cool the chambers.
There is a low temp table and a high temp table that are shown below.
The variable at $8602 determines which one is used.
Code:
;----------------------------------------------------------------
; PWR ENRICH TPS THRESHOLD vs RPM
; FOR NORMAL COOLANT
; *** WOT ***
;
; TBL = TPS% * 2.56
;----------------------------------------------------------------
; VAL %TPS RPM
;--------------------------------------
L8603: .byte 0x80 ;=128, 50 400
.byte 0x80 ;=128, 50 1200
.byte 0x80 ;=128, 50 2000
.byte 0x9A ;=154, 60 3200
.byte 0xB4 ;=180, 70 4800
;----------------------------------------------------------------
;----------------------------------------------------------------
; PWR ENRICH TPS THRESHOLD vs RPM. FOR HIGH COOLANT
; *** WOT ***
;
; TBL = TPS% * 2.56
;----------------------------------------------------------------
; VAL %TPS RPM
;--------------------------------------
L8608: .byte 0x80 ;=128, 50.0 400
.byte 0x80 ;=128, 50.0 1200
.byte 0x26 ;= 38, 14.8 2000
.byte 0x26 ;= 38, 14.8 3200
.byte 0x26 ;= 38, 14.8 4800
;---------------------------------------------------------------- Thread Starter
Junior Member
Joined: Apr 2004
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From: St. Paul
Re: > PE, no change - Any ideas?
I'm sure that I'm just missing something simple here but waiting for one of you guys to explain it.
Thanks!
Todd
Joined: Apr 2004
Posts: 3,180
Likes: 3
From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Re: > PE, no change - Any ideas?
The Minimum Temp "for use of the high temp table" is what the variable does.
Naming issue is what caused the confusion.
95HawkCnvt,
As far as why you are running lean, Do the fuel psi check when running to be sure. Tape a gauge to the windshield is the best way. (outside of course)
If fuel pressure is ok then add more to the % change per RPM table.
Last edited by JP86SS; Oct 1, 2007 at 08:13 PM.
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Joined: May 2004
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Car: superrammed V
Engine: 396 SBC Speed Density
Transmission: 700R4
Axle/Gears: Dana44 3.45
Re: > PE, no change - Any ideas?
Have you patched the bin with the 8D PW limit calculation?
With bigger injectors constant and big displacement constant this can be the problem.
I really dont know if with the superAUJUP_3 the pacth is in.
-Beppe-
With bigger injectors constant and big displacement constant this can be the problem.
I really dont know if with the superAUJUP_3 the pacth is in.
-Beppe-
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Joined: Feb 2005
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From: GA
Car: '90 C1500
Engine: SBC MPFI
Transmission: 4L80e
Axle/Gears: 4.30
Re: > PE, no change - Any ideas?
If you are talking about the item at location 8602 then yes.
The Minimum Temp "for use of the high temp table" is what the variable does.
Naming issue is what caused the confusion.
95HawkCnvt,
As far as why you are running lean, Do the fuel psi check when running to be sure. Tape a gauge to the windshield is the best way. (outside of course)
If fuel pressure is ok then add more to the % change per RPM table.
The Minimum Temp "for use of the high temp table" is what the variable does.
Naming issue is what caused the confusion.
95HawkCnvt,
As far as why you are running lean, Do the fuel psi check when running to be sure. Tape a gauge to the windshield is the best way. (outside of course)
If fuel pressure is ok then add more to the % change per RPM table.
Joined: Apr 2004
Posts: 3,180
Likes: 3
From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Re: > PE, no change - Any ideas?
The switchover point for WHEN to use the HIGH TEMP table.
The tables have the TPS% where PE will become active (At a certain RPM level)
Has nothing to do with temperature.
BTW,
S_AUJP V3 has the patch in it.
Last edited by JP86SS; Oct 2, 2007 at 11:44 AM.
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From: garage
Engine: 3xx ci tubo
Transmission: 4L60E & 4L80E
Re: > PE, no change - Any ideas?
Like JP86SS said, PE MODE always happens. The temp. constant determines which PE table to use. A hotter engine uses a richer table for PE.
What is the fuel pressure and injector DC at the lean condition?
What is the fuel pressure and injector DC at the lean condition?
Thread Starter
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Joined: Apr 2004
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From: St. Paul
Re: > PE, no change - Any ideas?
I'm going to go out & run it to see what happens to FP, but I just checked my log and the base pulse width for the injectors is at approx. 9.2 ms when it starts to go lean and then climbs to about 10 ms and starts going back down to about 9.3. All the while it is getting leaner.
Todd
Todd
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Joined: Apr 2004
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From: St. Paul
Re: > PE, no change - Any ideas?
So it looks like fuel pressure is indeed the culprit here. I'm thinking that it may be the filter because it drops to 20 psi immediately on WOT then will go down even further (17 psi before I let off so it didn't go too lean) if you stay in it.
This was an obviously likely scenario but of course I wasn't thinking about it right away. Thanks for the help guys!
Todd
This was an obviously likely scenario but of course I wasn't thinking about it right away. Thanks for the help guys!
Todd
Joined: Mar 2000
Posts: 1,692
Likes: 1
From: Corona
Car: 92 Form, 91 Z28, 89 GTA, 86 Z28
Engine: BP383 vortech, BP383, 5.7 TPI, LG4
Transmission: 4L60e, 700R4, 700R4..
Axle/Gears: 3.27, 2.73
Re: > PE, no change - Any ideas?
So it looks like fuel pressure is indeed the culprit here. I'm thinking that it may be the filter because it drops to 20 psi immediately on WOT then will go down even further (17 psi before I let off so it didn't go too lean) if you stay in it.
This was an obviously likely scenario but of course I wasn't thinking about it right away. Thanks for the help guys!
Todd
This was an obviously likely scenario but of course I wasn't thinking about it right away. Thanks for the help guys!
Todd
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