82 Crossfire ECM questions
Thread Starter
Pro
Joined: Jan 2000
Posts: 672
Likes: 0
From: Flanders N.J.
82 Crossfire ECM questions
With a few glitches recently, we have decided to replace the ECM in my car.
I had a hard time getting one as GM advised they are discontinued, and
finally did purchase one from Mid America. All other suppliers were sold out.
The question I have is does anyone know if the ECM can be re-built and
if so, who can do that type of work?
Mid America wants a core charge, so apparently someone is able to re-build these, but everyone I have spoken to says no.
I was actually thinking about having mine re-built and holding on to a spare in case they become extinct.
The other question was would an 84 ECM work in an 82??
Thanks for any information...
I had a hard time getting one as GM advised they are discontinued, and
finally did purchase one from Mid America. All other suppliers were sold out.
The question I have is does anyone know if the ECM can be re-built and
if so, who can do that type of work?
Mid America wants a core charge, so apparently someone is able to re-build these, but everyone I have spoken to says no.
I was actually thinking about having mine re-built and holding on to a spare in case they become extinct.
The other question was would an 84 ECM work in an 82??
Thanks for any information...
Pro
Joined: Mar 2002
Posts: 511
Likes: 0
From: St. Louis MO
Re: 82 Crossfire ECM questions (Peter Bilella)
Call Carquest, Napa, or an All Pro Parts store. They ussually send that stuff out to a place that rebuilds them. I took an 84 Cross Fire computer to Carquest and had a rebuilt one in a few days.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (Peter Bilella)
Yes, the MA ECM's are rebuilt. I don't remember who did it for them though. Most ECM's for older cars are remanufactured by Delphi.
The 84 ECM is a plug & play replacement for the 82 IF you get one for an auto tranny and use the 84 prom in it. The 82 & 84 prom are not interchangeable. The 84 ECM is about 1/2 the size of the 84 and is able to control the system better too.
Thr 82 ECM is the 1225550 , the 84 auto ECM is the 1226026
Marck
The 84 ECM is a plug & play replacement for the 82 IF you get one for an auto tranny and use the 84 prom in it. The 82 & 84 prom are not interchangeable. The 84 ECM is about 1/2 the size of the 84 and is able to control the system better too.
Thr 82 ECM is the 1225550 , the 84 auto ECM is the 1226026
Marck
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (Peter Bilella)
I'm not sure if there's an updated 84 prom, there probably is. You might want to ask on the crossfire vault if someone knows.
If you swap to the 84 ECM you must replace the prom.
For the 82 there's an updated prom that eliminates the TCC lockup in lower 3 gears so something similar must be available for the 84.
Marck
If you swap to the 84 ECM you must replace the prom.
For the 82 there's an updated prom that eliminates the TCC lockup in lower 3 gears so something similar must be available for the 84.
Marck
Le Mans Master
Joined: Apr 2001
Posts: 6,161
Likes: 0
From: Easton PA
Re: 82 Crossfire ECM questions (Twinnie)
Twinnie, and idea where one could get a replacement PROM for my 82 ECM?
Interested in getting rid of the lock up situation.
Thanks
[Modified by 82dukman, 4:25 PM 9/26/2002]
Interested in getting rid of the lock up situation.
Thanks
[Modified by 82dukman, 4:25 PM 9/26/2002]
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (82dukman)
Chevy dealership? Dunno. The hypertech chip takes care of it too but don't expect any performance gain from that chip. If you buy it buy it for TCC lockup.
Maybe some of the guys on the vault have a source for the proms.
Marck
Maybe some of the guys on the vault have a source for the proms.
Marck
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
Re: 82 Crossfire ECM questions (Twinnie)
The 84 ECM is a plug & play replacement for the 82 IF you get one for an auto tranny and use the 84 prom in it. The 82 & 84 prom are not interchangeable. The 84 ECM is about 1/2 the size of the 84 and is able to control the system better too.
Is the 84 a faster ecm than the 82? I know you said it, but, to ask again, the 84 ecm is really a plug and play replacement of the 82 ecm (with an 84 prom of course). Is this a worthwhile change? There is no way I can attempt the 7747 upgrade.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (Larry82)
The 84 ECM has the same Motorola processor as the '7747 if I'm not mistaking. It's a tad faster than the 82 but more importantly, it handles the engine parameters a lot better. On a eadout w/ a scanner the 84 ECM also gives out more info than the 82 one.
If you can get your hands on a good 84 ECM & prom I say do the swap, it will probably improve the idle quality on mildly modded motors.
I had one and it worked a lot better than the 82 ECM.
Marck
If you can get your hands on a good 84 ECM & prom I say do the swap, it will probably improve the idle quality on mildly modded motors.
I had one and it worked a lot better than the 82 ECM.
Marck
Drifting
Joined: Feb 2002
Posts: 1,987
Likes: 3
From: Manchester, Dead Center in the Middle of TN 25 miles to Jack Daniels,10 miles to Geo Dickle, and .8 mile from the Liquor Store at I-24 Exit 114
St. Jude Donor '05
Re: 82 Crossfire ECM questions (Twinnie)
At one time I had posted to someone that the ECM they were needing was not only for a Corvette. I believe it was for an '81 though. The '81 uses the same ECM as a Buick Regal or Cutlass, GP and many others and oh yes even a CHEVETTE. The only difference is the PROM in '81.
This may hold true in '82 as well. Marck do you know if the Crossfire created a seperate need? I can go and have it serched at my friends Salvage Yard on his Hollonder Interchange Program if needed.JIM :seeya
This may hold true in '82 as well. Marck do you know if the Crossfire created a seperate need? I can go and have it serched at my friends Salvage Yard on his Hollonder Interchange Program if needed.JIM :seeya
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (PROSOUTH)
The crossfire has a seperate ECM for some reason. The 84 has the digi dash stuff in it (not used when you plug it into the 82) and the 82 is the only one using the huge 1225550 ECM.
You could use a different TBI ECM but the problem is you will need both a PROM for it and the correct V8 calpack. The '7747 is the most hacked ECM out there and all the info is available for tuning it.
Corvette Fever tried it w/ a Camaro ECM wich is 8192 baud (instead of the 160 for the others mentioned above) but that one was difficult to tune (no info available, you'd have to hack the code yourself, very time consuming) and it used a MAT so you'd have to install one & modify the harness.
"Hollonder Interchange Program" ???? what is that? :)
Marck
You could use a different TBI ECM but the problem is you will need both a PROM for it and the correct V8 calpack. The '7747 is the most hacked ECM out there and all the info is available for tuning it.
Corvette Fever tried it w/ a Camaro ECM wich is 8192 baud (instead of the 160 for the others mentioned above) but that one was difficult to tune (no info available, you'd have to hack the code yourself, very time consuming) and it used a MAT so you'd have to install one & modify the harness.
"Hollonder Interchange Program" ???? what is that? :)
Marck
Melting Slicks
Joined: Aug 2000
Posts: 2,961
Likes: 1
From: Sealy Texas
Cruise-In III Veteran
Re: 82 Crossfire ECM questions (Twinnie)
Marck, Corvette Fever used an '8746 ECM, not one that uses a MAT. It's exactly the same (internally) as a '7477, but has a few extra "features" that the '7747 doesn't. It *IS* hacked, also. The '8746 uses an IAT (intake air temp) sensor, and has the controls for all the A.I.R. system. It also had "lean cruise" mode which allows you to get better gas mileage on the highway.
The '84 ECM puts out LESS info (only 5 bytes of data) but more often (every 1/4 second) than the '82 and '7747. They both put out 20 bytes of seperate data per second.
The '84 ECM puts out LESS info (only 5 bytes of data) but more often (every 1/4 second) than the '82 and '7747. They both put out 20 bytes of seperate data per second.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: 82 Crossfire ECM questions (Ken73)
Oh yeah, IAT, not MAT. Oh well :)
I mean the 84 ECM has more diagnosis paramters, if you hook it up to a scanner you get 5 or so more fields of info than w/ the 82.
I've been out of this ECM stuff for too lomg ;) Gotta do some reading up on the stuff you guys do.
I mean the 84 ECM has more diagnosis paramters, if you hook it up to a scanner you get 5 or so more fields of info than w/ the 82.
I've been out of this ECM stuff for too lomg ;) Gotta do some reading up on the stuff you guys do.
