funstick

fo those of you looking for the ultimate undehood ECM. the 1228708 is working. heres what i had to do.

You must use a 1228708 memcal.

the chip must be burnt from 04000 stating adress.
the first 000-3fff must be filled with FF if its not the damn thing will wig the hell out. dont ask me im not sure why yet. its gotta be a restart/ memcal pull up pull down vector thing. but it works

do not hook anything at all peiod to the 1x refernce line at all. it will drive the timme module crazy. here is the pinout for running the 1228708 with $58 code.

Warning this is bench tested and run on one vehicle only



connector function wire color
A1 IAC "a" high blu/wht
A2 IAC "b" low grn/blk
A7 IAC "a" low blue/blk
A8 IAC "b" high grn/wht
A9 Coolant fan relay
A11 Wastegate contol
A22 ECM gound blk

B1 Check Engine Light tn/wht
B5 ALDL SERIAL Orange/ pin M @ALDL
B10 Ignition Run/Start Red

C1 +BATT Orange
C3 Bst/Bypass tn/blk
C4 Mat tan
C5 Sensor ground black
C7 +5v REF gray
C9 EST white
C10 sensor ground black
C12 +5 v REF gray
C15 TPS drk blu
C16 CTS yellow
C22 MAP green

D1 Jumper to D5 inj sense [p/h 4 cyl] blue
D4 Jumper to D8 inj sense [p/h 4 cyl] tan
D7 Fuel pump relay grn/wht
D9 Inj 1@4 lt blue
D12 Ing module ground blk/ed
D12 ECM ground black
D13 REF pulse ing module ppl/wht
D14 Inj drive 2@3 lgt green
D16 + BAT orange
D19 ALDL ground blc/wht
D21 ECM ground black


anyways folks there it is. a pinout that makes a commonly avaiable ECM work. you can find these ECM in 89-93 pontiac grans ams with a 2.3 dohc quad 4 also any other w body with a undehood ECM of a simila models yrs should have the same ECM.

dohc quad 4 2.3 underhood ECM in pontiac buick and oldmobile vehicles.


as stated above all things must be done as so to make it work. im gonna ty to find a way to make it run in bank/bank soon enough. i think all of that is being handled VIA a timmer module on the motherboard. so once i find a good input fo the cam sensor ( which should be a hall effect) with a ref pulse ratio of 2ref pulse per one ef pulse ) a simple single magnet 5v hall effect should work. but im not sue how the $58 code will eact to anothe timmer input comming in. i can only verify what ive tested.

If you do this please add your input here.

Also to convert this into a 730 style pinout simply use the 1227727/1227749 conversion chart available on ludis langens webpages. although the egula 1227749 pinout should wok make sure not to add the 1x ref signla getting it mixed. but it should be plug and play.
Sean out and i hope somebody appreciates this.

92GTA

iTrader: (11)

So I guess the same goes for the 1228707 ???

Sucks because I have a 305 and I presume the MEM-CAL you had to use had a CAL-PAK for a 350 right?

BMmonteSS

what kind of injectors will this thing handle? I need an ecm that will take 8 low impedence 36# turbo coupe injectors.

funstick

no it will do 4 low impdence injectors. but it can be modified just like a 1227749 to run 8 by changing the fets and the sense resistors.

92GTA

iTrader: (11)

Do you know where I can send off an ECM to have this done? I was going to buy a 7749 but I figure I may as well buy an 8707, same goes for the 8707 right?

So what's with this MEM-CAL thing? I've got a 305 and have 305 MEM-CAL's already modded with 29C256's already inside them. Because of this it looks like I'll just have to use a 7749 right?

BMmonteSS

Here's a slightly better question where might one find a DIY guid to changing out the fets?

funstick

has anybody else tested this out other then me. it would be nice to get some parrallel testing to ensure i havent just encountered a fluke.

Dave_Jones

http://mywebpages.comcast.net/p-928/749mods.html

Justafour

Nice work. but are you confident that your pinouts for C12 and C15 are correct ?

On a few other diagrams C15 is an input and C12 is +5 volts...
I could be mistaken, but on my car the input is on C15

funstick

yes i tested it via the aldl. the tps sweep works.

Justafour

If the wiper and the +5 volts are swapped to the pot, it will still give a correct reading, but that dosen't mean that the information about the two pins is correct.

I could be completely off here, but I've got several GM diagrams that have it opposite to what you have shown. But it would not be the first time that a GM/Delco wiring diagram was incorrect.

TheGreatJ

Having them reversed will cause excessive current through the pot. at low throttle openings, which means the car is going to eat TPS's over the long term. Might want to double-check to be sure.


My database at work shows C15 as TPS position as well (for a '92 Grand Am.)