Ok. This is where I'm at so far ...

Tactrix Openport EcuFlash and MMCFlash aren't capable of flashing '97 Montero Sport ECMs. So, that's out. I have an email out to Dynotronics with pictures of the '99 and '97 ECM to see if they can do it. Nothing back yet.

I'm STILL trying to get some definitive information on whether AEM's piggy-back F/IC will allow you to drop timing and fuel on a naturally aspirated vehicle. I'm starting to think a parallel install of a Megasquirt isn't such a bad idea. <img src="/forums/images/graemlins/confused.gif" alt="" />

I picked up a '99 3.5L ECM this week and pulled the pin-outs for the '99 3.0/3.5 and '97 3.0 from the Mitsubishi service manuals. (see PDFs at the bottom of the paged linked to down below)

I've went through (several times) both the '97 ECM and '99 PCM pin-out diagrams and the only thing that differs in between the two is:

1) '99 automatic transmission PCM has a pin for neutral/park & drive.

2) '97 manual transmission ECM has a pin for ABS.

I know I can ignore #2 because neither of my '97s have now or ever had ABS, so it obviously can't be doing anything.

Does ANYONE know what #1 is for?? Even the techs can't explain to me what that's supposed to do and whether it can trigger CEL.

According to the service manuals, there's no difference in sensors (voltage, ohms, etc.), both have all the same input/outputs - so other than the above there's nothing added or missing between the units.

My BIG question is:

If I were to wire all the pins from my '97 harness into the locations specified by the manual for the '99 PCM, will it work??? There seem to be a LOT more pins on the connectors for both years than there are pin-out specifications in the manuals.

My idea currently is to wire the new PCM into my '97 harness. Prefereably without hacking the original harness. I have an email with pictures of both unit's plugs out to Boomslang. I'm reasonably sure that they have/or can get plugs for the '97, but the '99 may be a different issue. I guess I'll find out. If they have plugs they're happy to wire up a one end of a short conversion harness to go from one to the other and then I can do the other end based on the documentation I have.

Otherwise, I'm going to be looking for a '99 harness I can scavenge the PCM plugs off of, hack the plugs off my existing '97 harness and wire the new plugs in. That's not a plan I'm happy with if I have no idea if it'll even work. <img src="/forums/images/graemlins/frown.gif" alt="" />

Any insight would definitely be appreciated. I know a lot of you guys have done a lot more with automotive wiring than I have.

'97-'99 Montero Sport ECM/PCM Info

BTW, if any of the Sport people here are interested, I'm trying to document the '97-'99 ECM/PCMs - P/Ns, production years, pin-outs, images. I'd welcome the Mitsubishi service manual pin-outs for '98 if anyone has them along with clear pictures (top, plugs, and PCB) of any of the units I'm missing.

Edit:

WOOHOOO! Boomslang just emailed back. They have plugs and can make harnesses for both the '97 green 4 plug ECM ($125) and the '99 black 4 plug PCM. I'm waiting for whether they'll wire a cross-over '97 female green -> '99 male black harness or if I have to buy a flying lead and do the other end myself.

Edward