4.1s were not very popular. The early ones (at least the ones in the "big" cars) were notoriously unreliable. I would be surprised if anyone has messed with them. OTOH, if yours is a 91, I would be surprised if the AUMF chip didn't work correctly. UNLESS they changed to a 4T60E instead of the F7. I suppose that's possible, but the Allante service manual specifies the F7. (I'll have to see what year my Allante manual is.)
Edit - A little more searching found this. It's a 2240 PCM with the ADBC EPROM. It supposedly came from a 1993 Seville.
Thanks for the link Raydar. That ecm would work for me I believe. But I would still have to come up with eprom# 27c512 for it to work with my engine and transmission. Then I would need to get it re-programmed. I'm wayyy out of my comfort zone here. Can a blank chip be purchased and the necessary files loaded on to it? Or maybe I could try to find a used computer and eprom at a salvage yard and have that one programmed? I've been getting some of my info here..http://westersgarage.eidnet.ca/obd1.html . I'd love to get started on this project but I'm reluctant until I'm reasonably sure I can get it to work.
IMHO, the ECM that you have should work. It's probably a "service replacement" for the 2240. I don't really understand the EPROM that you have, but there's at least an outside chance that it's been reprogrammed with the correct stuff to run your engine. Especially if it all came out of the same car. All of the Caddy chips are a variant of the 27512. The ones I have are 27SF512, I believe. But they should all work essentially the same. If yours has a clear window under the sticker, it will require a UV eraser. The SF versions are EEPROMS. They do not require a UV lamp to erase them before reprogramming. Blank ones are available on eBay. $12 for two of them. (They say "for Honda", but the chip can't tell the difference. )
There's more to programming than I am prepared to get into, tonight. I have to get up at 5 AM. With that said, I would try to install yours as it is, and see what happens. Or ask Ryan to mod an AUMF (common Allante) program to do what you need. I have that file, if he doesn't. I can send it to you or to him. He should have a source for the blank EEPROMS, too.
[This message has been edited by Raydar (edited 10-21-2019).]
IMHO, the ECM that you have should work. It's probably a "service replacement" for the 2240. I don't really understand the EPROM that you have, but there's at least an outside chance that it's been reprogrammed with the correct stuff to run your engine. Especially if it all came out of the same car. All of the Caddy chips are a variant of the 27512. The ones I have are 27SF512, I believe. But they should all work essentially the same. If yours has a clear window under the sticker, it will require a UV eraser. The SF versions are EEPROMS. They do not require a UV lamp to erase them before reprogramming. Blank ones are available on eBay. $12 for two of them. (They say "for Honda", but the chip can't tell the difference. )
There's more to programming than I am prepared to get into, tonight. I have to get up at 5 AM. With that said, I would try to install yours as it is, and see what happens. Or ask Ryan to mod an AUMF (common Allante) program to do what you need. I have that file, if he doesn't. I can send it to you or to him. He should have a source for the blank EEPROMS, too.
Just a thought. I use the 27SF512 flash memory chips as well and not the original eprom 27512 that GM used. The flash chips are easier to program and they work but I am just wondering if they are as resistant to heat as the original chips that may be industrial/automotive temp rated. Commercial chips are rated 0-70* C That's 32*-158* F. Industrial/automotive chips are rated to +85C* which is 185*F .
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Does anyone have that programming software? The links don't work...
Tunercat sold a N93 definition file to go with their ECM editing software. It works with the Cadillac Deville 240 ECM but not sure about the Allante ECM.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I'm running a DeVille ECM with my Allante intake. I can't believe no one's made a TunerPro RT .xdf file yet...
Low demand to tune that ECM, hence no further development of editing tools. I believe that the Deville ECM would work with the 4.5L Allante engine but with a few small changes to the fueling and perhaps the timing. .
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I use TunerCat's software to do all my Caddy ECM/PCM tune file editing. Unfortunately, they don't support the 1227750 computer which is what my database says the ADBC chip was used in. (ADBC = 1987-88 Allante 4.1L).
TunerCat does indeed support the 4.5L Allante PCM (16132240). I also have a source for 27SF512 flash memory chips.
Pauljt - do you have a 4.1L or 4.5L Allante engine?
------------------ More is more. Less is not enough. Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com
The problem is that the Allante 4.1-4.5 87-89 used the 1227750 with a 27c256 PROM, the 90-up with 16132240 used a 27C512 PROM. Nothing interchanges. Been searching for a 1227750 definition file or schematic but nothing exists. Is anyone working here ?
Have a collection of .bins (1989 ANSU and a few others) but guess will just have to figure out.
[This message has been edited by padgett (edited 09-03-2021).]
The 4.5 hardware should be the same for all years of Allante. (I realize that you've "been there" already, but the easiest way to tell what you've got, other than part numbers, is that the 4.1 had EGR. The 4.5 did not.)
With all of that said, I would be inclined to just use a 2240 with the AUMF bin.
From Tunercat... CD1 16132240 90 Cadillac LW2, 4.5L, V8 (ATTL) (*This would likely be the PFI 4.5 in the Deville, among others.) 91 - 92 Allante LQ6 4.5L V8 (AUMF) 27C512
Since there is some question regarding your ECM and harness, you will need to make sure that your harness is wired correctly for the 2240, if that's what you use. If the other ECM is different, the pinouts may very well be different as well. I have the Allante manual. I can shoot you pics of the connector pinouts, if you need. (In case I lose this thread, feel free to shoot me a PM, if you need to.)
[This message has been edited by Raydar (edited 09-03-2021).]
OK am getting much deeper in this than sane but the problem with the early (87-89) Allante is that it did things that no other ECM did. For example the cooling fans are not relay driven, but have a module that adjusts the radiator fan speed by a Pulse Width Modulated (PWN) signal from the ECM and expects the same in return NOT on the ALDL line. Expect I'll just have to work through all 19k lines of code.
OK am getting much deeper in this than sane but the problem with the early (87-89) Allante is that it did things that no other ECM did. For example the cooling fans are not relay driven, but have a module that adjusts the radiator fan speed by a Pulse Width Modulated (PWN) signal from the ECM and expects the same in return NOT on the ALDL line. Expect I'll just have to work through all 19k lines of code.
I'll agree, use the 2240 ECM and you won't have to worry about so many small items. You can use the 27SF512 flash memory instead of the 27C512 eprom for ease of changing the program.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
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