THE OBD1.5 to OBD1 Conversion Thread

[robertisaar]

I'm reading 777727 on your attachment, not the 1227727.

You say the 16184164 has a PROM? Are the harness connectors the same?

well, thats just the aftermarket part number for a remanned ECM...

i don't know about the 16184164, i've never seen one before. i actually didn't know it existed until now...

[robertisaar]

just took a look on rockauto again, apparently the 16184164 was only on the 93 3.1 lumina, none of the other w-bodies...

and it looks like a regular PROM-swappable ECM(and it doesn't say otherwise), but i wouldn't know what codemask it runs on

[robertisaar]

i might have figured something out.

rockauto, checked the 93 GP SE with 3.1, there's a couple flash PCMs there and a couple of regular ones. it looks like the california emissions models got a flash PCM while the rest got regular ones...

[ForcedFirebird]

Hmm. That looks like the LT1 connectors too.

Need to find similar connectors to the ones in the car now (like the diagram in the '93 pdf), or repin a connector from an under hood PROM based ECM. I know a '94 ECM from the L body (OBD1.5) is a direct fit and will run/drive fine in an f-body, probably just has a slightly different tune flashed to it.

I was going to piggyback a '7730 and run the wires in the cabin, but I think it migh just be wiser to do a full swap after reading through these pinouts.

The LT1 connectors/feeds are a lot different than the V6 stuff, and has a lot more/different features and is probably not the way to go.

[robertisaar]

L-Body... beretta? i think that would have electronic tranny controls...

[ForcedFirebird]

Yes. That's correct, same with the '94 f-body. I didn't try it on a '93.

Looks like the best option is a 122727 from a '93 Lumina. Do you know if that was an e-trans? If so, are there any '727's that had a non-E trans?

Also this sucks because I have a pile of '7730's and connector pigtails, I was hoping to use one Just think it's easier to go under-hood)...

[robertisaar]

Yes. That's correct, same with the '94 f-body. I didn't try it on a '93.

Looks like the best option is a 122727 from a '93 Lumina. Do you know if that was an e-trans? If so, are there any '727's that had a non-E trans?

Also this sucks because I have a pile of '7730's and connector pigtails, I was hoping to use one Just think it's easier to go under-hood)...

john, i don't know what exactly you're trying to do, but....

94 f-bodys had electronic trannies, but the line pressure was controlled by the PCM, as far as i know, the tune that the L-bodies use doesn't adjust anything in that respect...(could burn up the trannys)

and no 1227727 ever controlled an electronic tranny(it can't from what i've been told). and i don't see why you can't use a 7730, same ECU as a 7727, just with different pinouts/connectors...

[ForcedFirebird]

john, i don't know what exactly you're trying to do, but....

94 f-bodys had electronic trannies, but the line pressure was controlled by the PCM, as far as i know, the tune that the L-bodies use doesn't adjust anything in that respect...(could burn up the trannys)

and no 1227727 ever controlled an electronic tranny(it can't from what i've been told). and i don't see why you can't use a 7730, same ECU as a 7727, just with different pinouts/connectors...

Ah. It was just a test anyways.

I need the weatherproof case is why I will have to go to the '727, rather than get another harness to move one of the ECM's I have inboard. I think the best option now is to leave the ECM where it is, use the same harness and just pin the wires into a '727 connector and be done with it. Just stinks because before I pull this engine out to do the hybrid swap, cam injectors etc, I wanted to get the ECM swapped so I could do any testing needed on a known good running engine rather than trying to tune on with a new ECM that may or may not have problems - and I'm sure you know how important a proper flat tappet cam break in is, and don't need to be trying to start a fresh engine unless I know the ECM is tip-top.

The original idea was to do a piggyback, but then I would be doubling up on sensors and since the '93 has a "700r4" with a slightly different case (aka 4l60). It only makes perfect sense to just swap it entirely.

Now to wait for yet another ECM to show up and search for a pigtail/connectors

[robertisaar]

Ah. It was just a test anyways.

I need the weatherproof case is why I will have to go to the '727, rather than get another harness to move one of the ECM's I have inboard. I think the best option now is to leave the ECM where it is, use the same harness and just pin the wires into a '727 connector and be done with it. Just stinks because before I pull this engine out to do the hybrid swap, cam injectors etc, I wanted to get the ECM swapped so I could do any testing needed on a known good running engine rather than trying to tune on with a new ECM that may or may not have problems - and I'm sure you know how important a proper flat tappet cam break in is, and don't need to be trying to start a fresh engine unless I know the ECM is tip-top.

The original idea was to do a piggyback, but then I would be doubling up on sensors and since the '93 has a "700r4" with a slightly different case (aka 4l60). It only makes perfect sense to just swap it entirely.

Now to wait for yet another ECM to show up and search for a pigtail/connectors

never had to break in a cam myself, but i have been explained the process/possible issues a few times...

[ForcedFirebird]

There are tons of connectors/pigtails on ebay for $15 (22.50 shipped) and have found some ECM's locally for $50. Too bad they closed at 1pm today, or I would already have one in my hand

Might even hit up the local u-pull-it on Monday and might get lucky to find one that I can clip the harness and maybe get the whole thing for $50

[robertisaar]

There are tons of connectors/pigtails on ebay for $15 (22.50 shipped) and have found some ECM's locally for $50. Too bad they closed at 1pm today, or I would already have one in my hand

Might even hit up the local u-pull-it on Monday and might get lucky to find one that I can clip the harness and maybe get the whole thing for $50

the local idea is probably the smarter option, that way you can actually get enough wire/inspect it before-hand. probably cheaper too...

[ForcedFirebird]

I might try the 95 LT1 ECM at a later date (in a 94-94). It appears it has the same connectors as the 94-95 V6 and will control the transmission, would just need re-pinning, fourth connector, and the Moates adapter. Also curious to see what kind of codes might be thrown because of the lower number of injectors, but that probably be tuned out. Am curious about the spark/ICM arrangement too.

[robertisaar]

the optispark is the only thing that really strikes as "not-compatible". i imagine as long as it gives the correct wave pattern(and you have the correct initial timing), the PCM could care less.

those were SFI right? that might cause issues(injectors)

i don't know what codemask the 95 is, but DA2/DA3 whichever it is for the earlier LT1s...... the fuel table is ridiculous, can't remember spark at the moment.

i'm not sure of the exact application, but here's one.

i would have to say its probably the most detailed OBD1 PCM ever. code59 might be close though.

[ForcedFirebird]

$59 is actually just a modified $58 SY/TY code that uses 3bar MAP, WBo2 among a few other features that's really awesome for boosted vehicles, but that's another thread

[robertisaar]

$59 is actually just a modified $58 SY/TY code that uses 3bar MAP, WBo2 among a few other features that's really awesome for boosted vehicles, but that's another thread

i know, but they have basicly made their own codemask at this point, and very detailed at that. if i go boosted with obd1, thats the route i'm going.