I looked at the tech article about programming your own prom, and I found out that my car doesn't have that little cartridge that holds the memcal and the PROM. The two are separate. How do I remove the PROM for programming? Its in some sort of plastic enclosure (not that chip that is shown in the article). I myself will not be doing the programming, my uncle will. He has re-done his 383 LT4 '92 Corvette, and my other uncle's '86 350 TPI (replacement engine). He will use the DIY ALDL cable hooked up to his laptop for readin the sensors on the car.

Oh and the actual PROM on my car is the 27C128, correct? Or is it the '256?

Thanks in advance

I believe the ecm you have is a 1227302 and it has a 2732 prom. A quick check at tunercat.com shows no def. file for your application. You might be able to switch to another ecm, say a 165 as it has the same connectors (I think) although I'm sure you'll have to do some repinning and other changes I bet. You could also swith to a 730 which is a little more involved but definitely the best choice.

Thanks for the quick reply. I see that's the same as the '85 TPI F-Body. Has anyone else on the board had luck programming this chip? I really don't want to do any conversions. Is the '85 TPI also not in a carrier as the Vette and 86-92 TPI? If so, how have the 85 TPI guys got it off the board?

Thanks again

It uses the same prom but not the same mask. Lots of applications use that prom, 747, 746, 148, 870, etc., but that doesn't mean they are the same, just physically use the same prom. To get it off you just pull up on it. You may have to pry it with a pick. Be careful as that little plastic cover does tend to break. The problem is that I don't think anyone makes a definition file for that mask so unless you are good at hacking you won't be able to program it. That is the reason for switching to another ecm that has a defined mask. The 730 ecm fits both v6 and v8 apps and there is even a winbin file for the v6 730 mask. However, I believe you would be able to use the v8 mask with a v6 using the cylinder select for v6 and the v6 memcal but with a v8 esc and knock sensor.

opps

How much will switching ECMs cost me??? (That does involve changin that whole metal thing that houses the PROM and memcal correct?)

Thanx

I have a 6d.ecu file for V6s.

My car that I reprogrammed was:

1988 Chevrolet Celebrity 2.8L V6
with MAF and MAP (SD)
1227730 ECM
27C256 EPROM
$6d mask

I made a "regular" reprogramation without scanner, laptop, cable, money, etc. in order to solve a hard knock, but the 6d works.

Regards,

Denis V.

Yes, the ecm is the silver case thing. That and the wiring harness. Can't quote you a cost but I can tell you what your best deal would probably be. Go to a junkyard and find a Beretta or Corsica with a 3.1L V6. Get the 730 ecm out of it and the complete harness. That cost me $30 by pulling it myself, YMMV. You will need wiring diagrams for the donor car and for the mask ($6D, $8D, $88) you plan to use. The same ecm with a different mask will use different ins and outs (I/O) so you gotta get the wiring right. THere is some work involved but you will be able to burn your own and if you decide to go V8 you'll be miles ahead. I have seen a $88 ecu for winbin on the DIY-EFI site. Just gotta look around where the info for the 730 ecm is. That mask is used on 91 3.1 V6 F body so it's probably the best to use along with AZTY? bin.

Oh no. This is getting more complicated than it has to. I'd have to replace the WHOLE wiring harness from the computer to the engine and sensors? I was only doing this so I could change my fan turn on temp and the idle speed. After that I would do testing with spark and whatnot.