Hello:

My cold start injector system on my 86 has gone for a crap.....

i will be diagnosing it at a later date, but would probably just like to block it off and re-tune my chip for extra fuel at start up.

I put in a generic arap $6e to test it and it fires up great.
My custom PCM4LESS $32 chip takes forever to catch without the CSI working properly while cranking...8+ secs. Starts and runs great when warmed up.

My question is, what do i have to change/add in my $32 bin to mirror the starting power of the ARAP $6E.

I would prefer to continue to use my $32 bin instead of starting over tuning the $6e

Thanks in advance

Ray

 

Probably just need to enrich cranking fuel. Some parts of the tunes will be compatible, use the compare feature to possible copy the cranking 6e fuel that is working well.

 

Good morning Ray! The 6e table to use is "Crank Fuel PW Multiplier vs Ref Pulse". The bottom eight entries are the ones to adjust from around .250 to .500.......... you play with them for the best results on your particular combo. For example, my car likes .250 in the first four pulses, then .500 on the next four. I didn't need to do anything w/ nine & beyond.

You'd need to look at the 32 XDF for something corresponding, but I really don't think it's there. That's precisely one of the big reasons folks go to 6e...........most guys w/ modded motors have deleted the 9th injector.

HTH

 

How have you been Tim...i did see that table in 6e...does not exist in 32.
I put values of 0.50 in the buckets 2-7 ..left 1st bucket at 0.00...fires up in 1 second. I was just hoping top duplicate the start-up in my 32 bin somehow.

I have had PCM tune it a few times as you know and just love the way it performs...not looking to switch over unless i have to.

got this from my post at Third Gen from Rrob

I would start with tables that affect the AFR/PW based on coolant temperature.

CRANK FUEL vs COOLANT Temp.
START UP ENRICH vs COOL

May need to lengthen the decay rate for the start up enrichment.

And possibly this one:

OPEN LOOP A/F % CHANGE VS COOL TEMP

Being a novice still..i could not possibly guess what to change the value to in those tables...any ideas?

 

I don't have a 32 XDF Ray and I'm not too familiar with those tables. I'll load one up later today or tomorrow & look at it.

Off the top of my head though I'd be inclined to follow RBob's advice as he *writes* the code the rest of us use The good thing about tuning is it's a lot like painting.........if you don't like the new color, you can paint right back over it. That's actually a real good way to learn these definitions.

 

To allow for crank fuel pulses up to 200 ms in $32 (just like $6E) double the following value:

;------------------------------------------------------
; CRANK FUEL vs COOLANT Temp.
;
;
; Table = Msec * (65.536 * 256) / LC36C
;------------------------------------------------------

LC36C: FDB 6554 ; Scale Factor for Max Crk P.W.

Then go back and rescale the crank fuel pw vs coolant temp table to show the correct pulse width by multiplying the conversion factor by 2 (if this table is not already linked to this scalar in your editor). Then simply copy the pw vs coolant temp values from a $6E bin.

Wait for a cold night (or drive to Kapuskasing) to see if it will start below -20 F in the morning. Adjust as required.

 

Were you drunk when you wrote this LOL

I read this 4 or 5 times and its a little confusing to me right now.

I think i'll stop at the liquor store on the way home from work....might make more sense to me after a few....

Thanks...i'll look at the code tonight with the tunerpro editor and see if i can understand it a little better.

BTW...The car has a very difficult time starting right now at about 8C or 45F

 

Thanks Tim...yes, i do read alot of what RBob writes over there.

I dont mind tweaking the tables a little bit to fine tune and learn that way. I have been tweaking my MAF tables a little more over the past year after working with you and have the BLM'S in a good area. Im still too new to actually start tuning from the beginning...and an 8+ sec crank time is the very beginning...would not know which way to move the values on those tables RBob listed...up ...down... or all around.

 

Ok what i did...i took this equation from the $32 xdf 0.390600 * X + 0.000000 and doubled the value of 0.390600 to 0.781200 and saved...it automatically doubled all the MSEC values in the $32 Crank Fuel PW vs Coolant table.

Then i manually changed all the msec values in the table to mirror the values in the $6e crank table.

This alone did not help my cold start..there must be more to making the 32 cold cranking fuel the same as 6e than just playing with this single table...maybe it cant be duplicated which is why people move to the $6e ARAP??

 

I had hoped this would work Ray, it would've been a nice fix for guys still using 32. There's another way to get at crank fueling though & that would be with your MAF table 1. Log your cranking A/F and raise the lower end of table 1 which in effect would give it more fuel in that narrow area. You'd need to feather the curve somewhat as it approaches your idle values, but that's a technique I've had success with in the past.

Of course you could always go to 6e.........that would just involve taking the time to copy n paste your existing bin.

 

You will also need to adjust the multiplier vs reference pulse to mimic $6E behavior which varies the multiplier as a function of the number of DRP's.

$32 has the pw multiplier set to 1.00 across the board, so it will tend to be too rich with the longer $6E pulse widths (especially during extended crank times).

$32 example for 0-128 DRP'S:

;------------------------------------------------------
;
; CRANK FUEL PW MULT vs DRP's
;
; Tbl = Mult * 256
;------------------------------------------------------
ORG $037F
;------------------------------------------------------
;
; MULT DRP'S
;------------------------------------------------------
LC37F: FCB 255 ; 1 0
FCB 255 ; 1 8
FCB 255 ; 1 16
FCB 255 ; 1 24
FCB 255 ; 1 32
FCB 255 ; 1 40
FCB 255 ; 1 48
FCB 255 ; 1 56
FCB 255 ; 1 64
FCB 255 ; 1 72
FCB 255 ; 1 80
FCB 255 ; 1 88
FCB 255 ; 1 96
FCB 255 ; 1 104
FCB 255 ; 1 112
FCB 255 ; 1 120
FCB 255 ; 1 128
;------------------------------------------------------

$6E varies the multiplier between 0 and 0.50 depending upon the pulse number to initially delay the fuel then deliver 1/2 the pulse and lean out.

$6E example for the first 16 DRP'S:
;----------------------------------------------
; CRANK FUEL PW MULT Vs. REF PULSE LT 17
;
; 10-18-1997 Dissassemby of ARAP Lines= 16
;
; TBL = 256 * MULT
;---------------------------------------------
ORG $038B ; MULT DRP'S
;---------------------------------
LC38B FCB 0 ; 0.000 1
LC38C FCB 0 ; 0.000 2
LC38D FCB 0 ; 0.000 3
LC38E FCB 0 ; 0.000 4
LC38F FCB 0 ; 0.000 5
LC390 FCB 0 ; 0.000 6
LC391 FCB 0 ; 0.000 7
LC392 FCB 0 ; 0.000 8
LC393 FCB 128 ; 0.500 9
LC394 FCB 128 ; 0.500 10
LC395 FCB 64 ; 0.250 11
LC396 FCB 64 ; 0.250 12
LC397 FCB 64 ; 0.250 13
LC398 FCB 64 ; 0.250 14
LC399 FCB 64 ; 0.250 15
LC39A FCB 64 ; 0.250 16
;---------------------------------------------

 

I do not have that table "Crank Fuel PW Multiplier vs Ref Pulse" listed in my $32 using Tunerpro.
Am i missing something or are you looking at something different than what im using

 

Thanks Tim...i'll look at the MAF1 table tonight...my fear is if i richen up the beginning of the table...will it show low BLM'S once in closed loop?

 

You have to add the multiplier table to your $32.xdf. What is shown is from the source hac (BUA).

 

Well...i copied the Crank Fuel PW Multiplier vs Ref Pulse data from the $6e xdf and pasted it into my $32 xdf...the table then showed up in tunerpro and i changed the top 8 values from 0.00's to 0.20. burned the chip and the car took even longer to start---didn't think it was going to start...must be more to it than that?

I am currently playing around with a $32b xdf i found that already has that Crank Fuel PW Multiplier vs Ref Pulse table plus a few more start up tables similar to $6e.

Im changing and copying over alot of data in the scalars and tables (some stuff i dont have in my original $32) to try to my match my current $32 bin...i'll post results when i burn the chip with the $32b.

 

When you copied the multiplyer table, did you also update the address (0x037F) and number of rows to fit the $32 bin (17 rows).

Note: the rows also have different meaning between 6E and 32. In 32, one row means 8 Drp's. In $6E one row means 1 Drp. so you need to adjust accordingly.

Verify that your addresses are correct so that you're not modifying the wrong data fields.

Download a copy of the BUA source hac as a reference. This shouldn't be hard to find.

Start with 0.5 in all rows. You can then get fancy and reduce the first row to 0.25 if you want and vary the later rows to lean things back out or even cycle rich lean to help it fire during extended cranking times. You need to figure out what pulse width and profile fits your injectors/engine for quick start up.

If you're still skeptical, you can log the bpw during crank with both $6E and $32 and compare your settings. Similar settings should yield similar results for a given coolant temperature. Scratch that idea: 160 baud logging with $32 is too slow to see effect.

Bottom line is that you have plenty of means in both $32 and $32B to achieve the desired results for cranking fuel. There's no magic in the $6E crank fueling tables or logic just increased maximum pulses (due to the scalar change and different handling of the multiplier as a function of drp).

Note: the scalar change to alow 200 ms and the multiplier change to 0.5 are essentially offsetting each other. You could always go back to the standard scalar and multiplier and have a similar result, except it wouldn't lean out the pw vs drp during extended cranking times.

Additional note: $32 and $32B share the same logic and tables (only the addresses are different). If you have different results between $32 and $32B it would suggest different settings between the two or that your editing the wrong addresses. Verify that your xdf changes are indeed correct.

 

I did not change anything when i pasted it into the xdf file.
I think it ended up with an address like 0x38F and 24 rows.

I will do it again tonight and change the address and number of rows. The table i looked at in the 32 hac had 17 rows...not 16.

Exactly what does the address do in the xdf/bin and where did you get the 0x037F from?