1227749 EEPROM Type

[Shannen Durphey]

Scott Flanagan wrote:
> 
> While at the junkyard the other day I luckily came accross two '88 Pointiac
> Grand Am Quad 4's.  They have the 1227749 with the uncommon Integrated
> Direct Ignition.  
This system is on all quad 4 engines.  The eprom in this application
is usually a 27c256, it is twice as large as the eprom in the syclone
or sunbird.  The data tables are in different locations, and this
makes for wacky values like 0 cylinders when read with promgrammer.  I
get the same values here.  You need to get a sunbird eprom.  
Shannen 

I am trying to work with an old reader, but I am not too
> sure what type of chip it is, or if it is too odd to read.  The chip in one
> of the ECU's has the number 27C256 on it, that is an original chip, which
> does not have a window for erasing.  My reader says it can read an I27256
> but it can't read it at all.  The other ECU is a remanufactured one, the
> chip does not have any numbers on it that are useful, but it does have a
> window for erasing things, my burner can read it but the information is
> garbled.  When loaded into Promgrammer it has some wacky values such as 0
> cylinders, etc.  Also, this is probably a dumb question but do you have to
> unsolder the chip from the long brown carrier?  Right now I have an adapter
> that I made that connects the brown carrier to the reader.  Thanks, I am
> very excited that I could finally find these ECU's and complete harnesses.
> 
>                             -Scott Flanagan
> 
> '80 Fiat Spider (Awaiting new FI and Turbo)