I have had a hard day,I'm doing an motor swap on a 86 bird.The 2.8 is not there,I traded for a 3.1 with harness and most of the accessories,The ECU or ECM or what ever the computer is called was not with the motor.Auto zone could get the computer but not the prom,salvage yard didn't want to sell me the one they had because they needed the numbers off the old one to make sure it was the right one.GM dealer needed the vin number off the vehical it came out of.Now were useing the machanical speedomiter off the old tranny and useing the tranny that came with the 3.1.I don't care if the air dosn't work or cruise controle.we have a map senser and stuff like that. the old fan is what we will be trying to use..Now some on here said any 3.1 computer would work,dose that also mean the basic operation of the car should work with any 3.1 computer prom in it or is this computer going to fry if it's not a match.

 

Here is a list of ECMs and BCCs that I was able to locate in a list of BCC codes from the moates.net site.

What you will want to do is match the tranny type you have, and check to see if any of the BCCs are available at the wreckers. The BCC is the 4 letter code, and will be found on both the ECM sticker and on the MEMCAL itself. Even if the ECM sticer says it is correct, I would still open the cover and check to make sure the MEMCAL matches.

There is one entry with a couple question marks beside it, this one seems a bit odd, in size and so I would try that one as a last resort. The "88" beside some of them is the code mask, which you won't need to worry about, I only included that for reference.

Year Eng Trans ECM BCC
1990 LHO Man 1227730 ALSX
1990 LHO Auto 1227730 ALSZ
1990 LHO Man 1227730 ALTB
1990 LHO Auto 1227730 ALTD

1991 LHO Man 1227730 ARPK 88
1991 LHO Man 1227730 ARPL 88
1990 LHO Auto 1227730 ARPM
1990 LHO Auto 1227730 ARPN

1990 LHO Auto 1227730 ATFM
1990 LHO Auto 1227730 ATFN
1990 LHO Man 1227730 ATRJ
1990 LHO Man 1227730 ATRK

1990 LHO Auto 1227730 ATXF
1990 LHO Auto 1227730 ATXH
1990 LHO Auto 1227730 AUJW
1990 LHO Auto 1227730 AUJX 88

1990 LHO Auto 1227730 AYCF 88
1990 LHO Auto 1227730 AYCH
1990 LHO Auto 1227730 AZTX ??
1990 LHO Auto 1227730 AZTY 88

1990 LHO Man 1227739 BAWX 88
1990 LHO Man 16196404 BMCD

 

I have a 730 available with an AUJW (pulled from a 91) MEMCAL if you need one. I also have an install guide for the later harness into the 86 if you need it. Question is, why are you insisting on swapping over the entire electrical system when all you need to do is put the engine in and hook things up using your existing harness? There are really very few changes to make to the 302 harness to run the 3.1.

:edit: You can run the engine with any MEMCAL, provided you find a way to tune the spark advance from an FWD chip, otherwise your engine will be running with the timing WAY retarded (60 degree offset in the FWD chips).

 

It would be 60 degrees advanced actually.

 

to make it a little more clear,I did not trade the 2.8 for the 3.1. I traded an 82ta for the 3.1 and tranny,ect. the 3.1 was missing the ECM. my 86 had a machanical speedomiter cable.we switched it into the newer tranny. should we have left the older tranny in the car or put the electronic cable back on or use the newer tranny with the old cable like we did? This computer thing has got me stumped,If I don't hook up the air or cruse controle and it dosn't matter to me if the overdrive locks in,why wouldn't any 90-92 computer and chip work? I just want the thing to drive down the road safely and not buck and jerk or back fire.You know just get around town.

 

You need a matching MEMCAL for your engine and tranny combination.

The 1227730 can be found in many cars from 1987 to 1994, that's not the part to be concerned with really, it's the MEMCAL that needs to match, because it has all the programming to run your combination of engine and tranny properly.

The only connection between the ECM and the cruise is a VSS wire, the only connection between the ECM and A/C is a sense wire for the ECM to idle up a few hundred RPM when the A/C clutch kicks in.

So hooking these up or not hooking these up will not really matter to how the engine runs, in the grand scheme of things.

 

this computer is a GM remanufactured service no.16198262 bottom of tag has 868262wz40663805this is the one I got from the auto salvage and race shop

 

That ECM is the equivalent of the 1227730. It's actually a secondary service number for it, that some would call an "updated" or "replacement" service number.

The MEMCAL is still the important part to verify.

 

this motor and tranny are supposed to be out of either a 91 or 92 firebird.take the plate off the top?I see AUAS on the prom

 

I took the cover off and it had AUAS and them small numbers but its a ECM for a 91 so whats that going to do?The guy said the motor was either a 91 or 92.what happens if I use the 86 auto tranny with this 91 motor and computer?

 

AUAS, is for 3.1L, but in an A-body. That would be the genII 3.1, that has the wrong spark offset and a few other variables will be different as well, but the major thing that is not right is the spark offset with that MEMCAL.

 

well I lost that money,He said it was for a 91 firebird 3.1 and voided my waranty because I couldnt give him any numbers off of the old ECM

 

The ECM itself will still be useable, just the MEMCAL has to be swapped for a proper one, or for an aftermarket EPROM, with adaptor, but I'm not sure I've seen any 3.1 F-body BINs posted.

 

are the codes the same on 91 and 92's as the ones you gave for the 90's

 

Maveric,We are not changing the whole electrical set up over,just the stuff related to the motor computer and related stuff

 

Note that since the '90 - '92 f-body's have VATs, you will need a VATs bypass module. Otherwise the ECM won't fire the injectors.

The MEMCAL BCC of AZTY is the last (newest) for the '90 - '92 MPFI set ups with the 700R4 tranny. Using a MEMCAL from a stick car won't lock up the TCC properly, so it is best to be avoided. Although if you do get a stick MEMCAL disconnect the connector at the transmission.

That will prevent the shift light from locking up the TCC. Which if it does will quickly destroy the TCC as it will lock up under heavy load.

As for AUAS, I don't believe that GM put VATs on the CELEBRITY & 6000 LE cars. So you can use that MEMCAL in a pinch. At least until you get a VATs bypass module and a copy of AZTY.

To use the AUAS MEMCAL open the EST/BYPASS connector. And leave it open. This will put the timing control in the distributor. It may also be helpful to bump the base timing up a few degrees. There is some built in timing advance, but it won't be as good as when the ECM handles the timing.

Once you get AZTY & the VATs bypassed, set the timing back to 10* BTDC and re-connect the EST/BYPASS connector. And you are good to go.

RBob.

 

Here is the GM part number for the AZTY MEMCAL:

PROM ID--------------Part Number-----------Description
AZTY 1331 ----------16171406 ----------Memcal(Federal-Auto Trans)

Should be able to get one from a dealer or maybe on line (gmpartsdirect?).

Note that AZTX is the California version of AZTY, which is the 49 state version of the calibration.

RBob.

 

thanks rob,where do I get a vats bypass moduel,where is the conector on the tranny that has to be disconected,we already disconected the line that gose into the speeomiter hole and put the older transmition machanical line in.Where is the EST/Bypass conector? On the EST? I'm dumb here! SORRY but what dose EST stand for?

 

Google the VATs box, will gets hits for them for sale along with how to build one.

Tranny connector: drivers side above the pan rail. Goes in straight down from above.

EST/BYAPSS: single wire/connector, tan w/black stripe, under hood, protrudes from harness in area of HVAC box.

EST: electronic spark timing.

RBOb.

 

thankyou again

 

OK this is good! all the stuff I have seen so far start with you having a key or interior wireing coming off the ignition.I don't have a vatts key or an orange wire on the colume because it's a 86 body.So will I be able to go straight into the ECM with a bypass module?Plus there are 14 or 15 different leveals of resistance.So I either go to buy 14 and try them one at a time.Or build all 14 myself and tie them in one at a time and atempt to start it.and thats only if everything was done right to start with!WOW what a puzzle?

 

http://www.fiero.nl/forum/Forum2/HTML/105361.html
http://newrockies.ca/

RBob.

 

Umm..just a shot in the dark here but the 1986 'Bird ECM (1227302) will run that 3.1 just fine? As for using the 1227730, that is a matter of hooking up the harness and burning yourself a new eprom chip. You can shut off VATS in the bin file and not have to worry about it? For the speedo, 86 was a mixed year. Some got electronic and some got mechanical(cable operated). Mine has the electronic speedo. There is a buffer box piggy backed on the ECM bracket with 2 plugs on it.

 

I have no way to burn a new Prom,And how can a maf ECM run a MAP system,Everyone so far has said the same thing,I either got to use the 3.1 ECM and get MAP sensor then get the ECM to bypass Vats or use 2.8 ECM change the EGR to the MAF type,Change the coil bracket so I get the Sensors that are on it mounted close to where they go an harness will hook up.Modify the intake or put the 2.8 setup on it.I'm trying the 2.8 stuff first as I won't have to cut the harness up as much.then if somthing dosn't work right I will cut and change as need be.Hopfully the maf sensor is good.I think they are alot of money if they are anywhere close to what one cost for a 350tpi 89 and older.Just in case anyone got one of them laying around colecting dust?Could the 2.8 ECM chip be made to run the 3.1 without having the vats?

 

It has been said a few times over that the 2.8 ECM will run the 3.1 just fine, you just have to install the supporting parts on the 3.1 as if it were a 2.8L, that means TB, the MAF sensor and a few other matching parts.

 

My 2.8 harness and associated parts have been running my 3.1 since 2004.

 

got it!