I am doing a speed density conversion on a mates firebird , it is using a 1227165 computer.

I have done a few of these before using the $5D code with no problems.

I am just about to change the couple of wiring pins required over when I cam across wires in B6 , B11 , C8 and C11 none of my wiring diagrams show any pins in these spaces and I would like to verify where in the wiring these are connected to before changing everything.

Does anyone have a wiring diagram showing these in use or can point me in the right direction.

 

Found this from a -89
B6- VATS
B11- Not used
C8- Top Gear input from transmission TH700
C11- Not used

/N.

 

Thanks , did some more research and came across the same info but still cant find what the wires connected into B11 and C11 are for , looks very factory so it must be in some wiring diagram

 

well, I checked ludis's site for the '165 schematic, and it lists those two pins as 'ESC' and 'MAP'. I don't know exactly how the vehicles are set-up where you are, but it looks like they are unused inputs to the A/D. So maybe the car has some other inputs that aren't common? very strange. You should trace them out and find out where they go, and post your findings, it would be interesting to know.

oh, ludis' site is : http://www.cruzers.com/~ludis/

it is an excellent site if you can read schematics.

good luck!

 

This is a full US spec car that has been imported , yes when using the $5D code they are MAP and ESC hence why I want to move some wires to these pins but they are already populated when they shouldnt be ?

Never come across this before , I have 2 vettes a Camaro and a Firebird in the shed at the moment ( all around 85 - 88 vintage and all using the 1227165 TPI setup ) , the others are as per the wiring diagrams and have these pins unpopulated.

One of GM's little mysteries

 

so Tom cat are you using the 165 ecm and changing it to map? Do you do that just by changing the prom?

 

Yep change the prom , remove the egr and airpump and move the maf input wire to MAP input and wire in a map sensor.

Then you need to start tuning using the $5D code which tunercat supports.

Do a search as I posted up how to a few years back.

Now if only I can discover what these extra wires in the harness where originally used for.

 

Tomcat...question please

Have you ever converted a 808 to 8192 baud by installing the missing UART?
Reason being I have a 165 in my 88 IROC TPI and was thinking of using a ($30.00AUS) 808 as a spare, being easy to find in Oz. I assume with minor changes I could use either SD or maf.

Wish I could help with the missing wires...according to my 88 Camaro (GM) service manual. Manual shows;

B6=VATS (PPL) 5 volts key&run
B11=Not used
C8=PSPS (Lt Blu) B+ key&run
C11=MAP signal (Lt Grn) key on 4.75volts, run 1.1 volts

This for a 305 Vin E (MAF)

 

Or you could use a (sometimes) $30 AUD 16183082/ 16206305 that is the VR/VS manual ECM that you sometimes find in Camira's and VN's as replacements. These have 8192 BAUD ALDL and you can run a $12 mask.

John

 

John is right , its easier to usse the VR/VS manual ECU which already has the 8192 baud.

I found the issue with the extra wiring - someone had beat me to the punch and gone Speed Density already and hidden the MAP under the dash.

Fixed the issues , tuned it up and it was all sweet.

Siggy , look me up sometime , I am in Maddington WA